VB.Net Tutorial/GUI/TextBox
Содержание
- 1 Change TextBox font by RadioButton and CheckBox
- 2 Comprehensive Demo for TextBox
- 3 Convert input value in a TextField
- 4 Copy selection text from a TextBox and paste to another
- 5 Create PasswordField by setting the TextBox.PasswordChar
- 6 Disable TextBox Context Menu
- 7 Display text file in a TextBox
- 8 Get input from TextBox and Set to Label
- 9 Get selected text in TextBox
- 10 Inherit TextBox to create custom control based on TextBox
- 11 Multiline Text Boxes
- 12 Numeric TextBox
- 13 Save text in TextBox to a file
- 14 TextBox Text Changed Event
Change TextBox font by RadioButton and CheckBox
<source lang="vbnet">Imports System.Windows.Forms public class RadioButtonControlFont
public Shared Sub Main
Application.Run(New Form1)
End Sub
End class
Public Class Form1
Public mysize As Integer
Public mybold As Boolean
Public myItalic As Boolean
Private Sub RadioButton1_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
CheckBox1.Checked = 1
End Sub
Private Sub CheckBox1_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox1.CheckedChanged
myItalic = Not myItalic
TextBox1.Font = New System.Drawing.Font("", mysize, Drawing.FontStyle.Regular)
If myItalic And mybold Then
TextBox1.Font = New System.Drawing.Font("", mysize, Drawing.FontStyle.Italic)
ElseIf myItalic Then
TextBox1.Font = New System.Drawing.Font("", mysize, Drawing.FontStyle.Italic)
ElseIf mybold Then
TextBox1.Font = New System.Drawing.Font("", mysize, Drawing.FontStyle.Bold)
End If
End Sub
Private Sub GroupBox1_Enter(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles GroupBox1.Enter
End Sub
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
mybold = False
myItalic = False
mysize = 25
End Sub
Private Sub RadioButton1_CheckedChanged_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles RadioButton1.CheckedChanged
mysize = 36
TextBox1.Font = New System.Drawing.Font("", mysize)
End Sub
Private Sub RadioButton2_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles RadioButton2.CheckedChanged
mysize = 25
TextBox1.Font = New System.Drawing.Font("", mysize)
End Sub
Private Sub CheckBox2_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox2.CheckedChanged
mybold = Not mybold
TextBox1.Font = New System.Drawing.Font("", mysize, Drawing.FontStyle.Regular)
If myItalic And mybold Then
TextBox1.Font = New System.Drawing.Font("", mysize, Drawing.FontStyle.Bold)
ElseIf myItalic Then
TextBox1.Font = New System.Drawing.Font("", mysize, Drawing.FontStyle.Italic)
ElseIf mybold Then
TextBox1.Font = New System.Drawing.Font("", mysize, Drawing.FontStyle.Bold)
End If
End Sub
End Class <Global.Microsoft.VisualBasic.rupilerServices.DesignerGenerated()> _ Partial Class Form1
Inherits System.Windows.Forms.Form
"Form overrides dispose to clean up the component list.
<System.Diagnostics.DebuggerNonUserCode()> _
Protected Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing AndAlso components IsNot Nothing Then
components.Dispose()
End If
MyBase.Dispose(disposing)
End Sub
"Required by the Windows Form Designer
Private components As System.ruponentModel.IContainer
"NOTE: The following procedure is required by the Windows Form Designer
"It can be modified using the Windows Form Designer.
"Do not modify it using the code editor.
<System.Diagnostics.DebuggerStepThrough()> _
Private Sub InitializeComponent()
Me.CheckBox1 = New System.Windows.Forms.CheckBox
Me.CheckBox2 = New System.Windows.Forms.CheckBox
Me.GroupBox1 = New System.Windows.Forms.GroupBox
Me.RadioButton1 = New System.Windows.Forms.RadioButton
Me.RadioButton2 = New System.Windows.Forms.RadioButton
Me.TextBox1 = New System.Windows.Forms.TextBox
Me.GroupBox1.SuspendLayout()
Me.SuspendLayout()
"
"CheckBox1
"
Me.CheckBox1.AutoSize = True
Me.CheckBox1.Location = New System.Drawing.Point(230, 34)
Me.CheckBox1.Name = "CheckBox1"
Me.CheckBox1.Size = New System.Drawing.Size(48, 16)
Me.CheckBox1.TabIndex = 1
Me.CheckBox1.Text = "Italic"
Me.CheckBox1.UseVisualStyleBackColor = True
"
"CheckBox2
"
Me.CheckBox2.AutoSize = True
Me.CheckBox2.Location = New System.Drawing.Point(230, 56)
Me.CheckBox2.Name = "CheckBox2"
Me.CheckBox2.Size = New System.Drawing.Size(48, 16)
Me.CheckBox2.TabIndex = 2
Me.CheckBox2.Text = "Bold"
Me.CheckBox2.UseVisualStyleBackColor = True
"
"GroupBox1
"
Me.GroupBox1.Controls.Add(Me.RadioButton2)
Me.GroupBox1.Controls.Add(Me.RadioButton1)
Me.GroupBox1.Location = New System.Drawing.Point(224, 85)
Me.GroupBox1.Name = "GroupBox1"
Me.GroupBox1.Size = New System.Drawing.Size(132, 77)
Me.GroupBox1.TabIndex = 3
Me.GroupBox1.TabStop = False
Me.GroupBox1.Text = "Font size"
"
"RadioButton1
"
Me.RadioButton1.AutoSize = True
Me.RadioButton1.Location = New System.Drawing.Point(6, 20)
Me.RadioButton1.Name = "RadioButton1"
Me.RadioButton1.Size = New System.Drawing.Size(59, 16)
Me.RadioButton1.TabIndex = 1
Me.RadioButton1.TabStop = True
Me.RadioButton1.Text = "Larger font"
Me.RadioButton1.UseVisualStyleBackColor = True
"
"RadioButton2
"
Me.RadioButton2.AutoSize = True
Me.RadioButton2.Location = New System.Drawing.Point(6, 42)
Me.RadioButton2.Name = "RadioButton2"
Me.RadioButton2.Size = New System.Drawing.Size(59, 16)
Me.RadioButton2.TabIndex = 2
Me.RadioButton2.TabStop = True
Me.RadioButton2.Text = "Smaller font"
Me.RadioButton2.UseVisualStyleBackColor = True
"
"TextBox1
"
Me.TextBox1.Location = New System.Drawing.Point(12, 12)
Me.TextBox1.Multiline = True
Me.TextBox1.Name = "TextBox1"
Me.TextBox1.Size = New System.Drawing.Size(195, 150)
Me.TextBox1.TabIndex = 4
Me.TextBox1.Text = "www.vbex.ru"
"
"Form1
"
Me.AutoScaleDimensions = New System.Drawing.SizeF(6.0!, 12.0!)
Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font
Me.ClientSize = New System.Drawing.Size(368, 174)
Me.Controls.Add(Me.TextBox1)
Me.Controls.Add(Me.GroupBox1)
Me.Controls.Add(Me.CheckBox2)
Me.Controls.Add(Me.CheckBox1)
Me.Name = "Form1"
Me.Text = "Form1"
Me.GroupBox1.ResumeLayout(False)
Me.GroupBox1.PerformLayout()
Me.ResumeLayout(False)
Me.PerformLayout()
End Sub
Friend WithEvents CheckBox1 As System.Windows.Forms.CheckBox
Friend WithEvents CheckBox2 As System.Windows.Forms.CheckBox
Friend WithEvents GroupBox1 As System.Windows.Forms.GroupBox
Friend WithEvents RadioButton2 As System.Windows.Forms.RadioButton
Friend WithEvents RadioButton1 As System.Windows.Forms.RadioButton
Friend WithEvents TextBox1 As System.Windows.Forms.TextBox
End Class</source>
Comprehensive Demo for TextBox
<source lang="vbnet">"Programming .Net Windows Applications [ILLUSTRATED] (Paperback) "by Jesse Liberty (Author), Dan Hurwitz (Author) "# Publisher: O"Reilly Media, Inc.; 1 edition (October 28, 2003) "# Language: English "# ISBN-10: 0596003218 "# ISBN-13: 978-0596003210 imports System imports System.Drawing imports System.Windows.Forms imports System.Text namespace ProgrammingWinApps
public class TextBoxes : inherits Form
dim yDelta as integer
dim yPos as integer = 20
dim txtSingle as TextBox
dim txtMulti as TextBox
dim txtDisplay as TextBox
dim btn as Button
dim txtBoxes(1) as TextBox
public sub New()
Text = "TextBoxes"
Size = new Size(450,375)
dim lblSingle as new Label()
lblSingle.Parent = me
lblSingle.Text = "Single Line TextBox:"
lblSingle.Location = new Point(10,yPos)
lblSingle.Size = new Size(150,20)
lblSingle.TextAlign = ContentAlignment.MiddleRight
yDelta = lblSingle.Height + 10
txtSingle = new TextBox()
txtSingle.Parent = me
txtSingle.Text = "Single Line"
txtSingle.Size = new Size(200, txtSingle.PreferredHeight)
txtSingle.Location = new Point(lblSingle.Left + _
lblSingle.Size.Width, yPos)
txtSingle.Multiline = false
txtSingle.BorderStyle = BorderStyle.Fixed3D
dim lblMulti as new Label()
lblMulti.Parent = me
lblMulti.Text = "Multi Line TextBox:"
lblMulti.Location = new Point(10, yPos + yDelta)
lblMulti.Size = new Size(150,20)
lblMulti.TextAlign = ContentAlignment.MiddleRight
txtMulti = new TextBox()
txtMulti.Parent = me
txtMulti.Text = "Multi Line"
txtMulti.Size = new Size(200,100)
txtMulti.Location = new Point(lblMulti.Left + _
lblMulti.Size.Width, yPos + yDelta)
txtMulti.AcceptsTab = true
txtMulti.Multiline = true
txtMulti.BorderStyle = BorderStyle.Fixed3D
txtMulti.ScrollBars = ScrollBars.Vertical
btn = new Button()
btn.Parent = me
btn.Text = "Show MultiLines"
btn.Location = new Point(lblMulti.Left + _
lblMulti.Size.Width, yPos + (5 * yDelta))
AddHandler btn.Click, AddressOf btn_Click
dim xSize as integer = CType((Font.Height * .75) * _
btn.Text.Length, integer)
dim ySize as integer = Font.Height + 10
btn.Size = new Size(xSize, ySize)
txtDisplay = new TextBox()
txtDisplay.Parent = me
txtDisplay.Text = ""
txtDisplay.Size = new Size(200,100)
txtDisplay.Location = new Point(lblMulti.Left + _
lblMulti.Size.Width, yPos + (6 * yDelta))
txtDisplay.Multiline = true
txtDisplay.BorderStyle = BorderStyle.FixedSingle
txtDisplay.BackColor = Color.LightGray
txtDisplay.ScrollBars = ScrollBars.Vertical
txtDisplay.ReadOnly = true
" Fill the array of TextBoxes
txtBoxes(0) = txtSingle
txtBoxes(1) = txtMulti
" Menus
" Edit menu items
dim mnuDash1 as new MenuItem("-")
dim mnuDash2 as new MenuItem("-")
dim mnuUndo as new MenuItem("&Undo", _
new EventHandler(AddressOf mnuUndo_Click), _
Shortcut.CtrlZ)
dim mnuCut as new MenuItem("Cu&t", _
new EventHandler(AddressOf mnuCut_Click), _
Shortcut.CtrlX)
dim mnuCopy as new MenuItem("&Copy", _
new EventHandler(AddressOf mnuCopy_Click), _
Shortcut.CtrlC)
dim mnuPaste as new MenuItem("&Paste", _
new EventHandler(AddressOf mnuPaste_Click), _
Shortcut.CtrlV)
dim mnuDelete as new MenuItem("&Delete", _
new EventHandler(AddressOf mnuDelete_Click))
dim mnuSelectAll as new MenuItem("Select &All", _
new EventHandler(AddressOf mnuSelectAll_Click), _
Shortcut.CtrlA)
dim mnuSelect5 as new MenuItem("Select First &5", _
new EventHandler(AddressOf mnuSelect5_Click), _
Shortcut.Ctrl5)
dim mnuClear as new MenuItem("Clea&r", _
new EventHandler(AddressOf mnuClear_Click))
dim mnuEdit as new MenuItem("&Edit", _
new MenuItem() {mnuUndo, mnuDash1, _
mnuCut, mnuCopy, mnuPaste, mnuDelete, mnuDash2, _
mnuSelectAll, mnuSelect5, mnuClear})
" View Menu items
dim mnuScrollToCaret as new MenuItem("&Scroll to Caret", _
new EventHandler(AddressOf mnuScrollToCaret_Click))
dim mnuView as new MenuItem("&View", _
new MenuItem() {mnuScrollToCaret})
" Main menu
Menu = new MainMenu(new MenuItem() {mnuEdit, mnuView})
end sub " close for constructor
public shared sub Main()
Application.Run(new TextBoxes())
end sub
private sub mnuUndo_Click(ByVal sender As Object, _
ByVal e As EventArgs)
dim i as integer
for i = 0 to txtBoxes.Length - 1
if txtBoxes(i).Focused then
dim txt as TextBox = CType(txtBoxes(i), TextBox)
if txt.CanUndo = true then
txt.Undo()
txt.ClearUndo()
end if
end if
next
end sub
private sub mnuCut_Click(ByVal sender As Object, _
ByVal e As EventArgs)
dim i as integer
for i = 0 to txtBoxes.Length - 1
if txtBoxes(i).Focused then
dim txt as TextBox = CType(txtBoxes(i), TextBox)
if txt.SelectedText <> "" then
txt.Cut()
end if
end if
next
end sub
private sub mnuCopy_Click(ByVal sender As Object, _
ByVal e As EventArgs)
dim i as integer
for i = 0 to txtBoxes.Length - 1
if txtBoxes(i).Focused then
dim txt as TextBox = CType(txtBoxes(i), TextBox)
if txt.SelectionLength > 0 then
txt.Copy()
end if
end if
next
end sub
private sub mnuPaste_Click(ByVal sender As Object, _
ByVal e As EventArgs)
if Clipboard.GetDataObject().GetDataPresent(DataFormats.Text) = true then
dim i as integer
for i = 0 to txtBoxes.Length - 1
if txtBoxes(i).Focused then
dim txt as TextBox = CType(txtBoxes(i), TextBox)
if txt.SelectionLength > 0 then
if MessageBox.Show( _
"Do you want to overwrite the currently selected text?", _
"Cut & Paste", MessageBoxButtons.YesNo) = _
DialogResult.No then
txt.SelectionStart = txt.SelectionStart + _
txt.SelectionLength
end if
end if
txt.Paste()
end if
next
end if
end sub
private sub mnuDelete_Click(ByVal sender As Object, _
ByVal e As EventArgs)
dim i as integer
for i = 0 to txtBoxes.Length - 1
if txtBoxes(i).Focused then
dim txt as TextBox = CType(txtBoxes(i), TextBox)
if txt.SelectionLength > 0 then
txt.SelectedText = ""
end if
end if
next
end sub
private sub mnuClear_Click(ByVal sender As Object, _
ByVal e As EventArgs)
dim i as integer
for i = 0 to txtBoxes.Length - 1
if txtBoxes(i).Focused then
dim txt as TextBox = CType(txtBoxes(i), TextBox)
txt.Clear()
end if
next
end sub
private sub mnuSelect5_Click(ByVal sender As Object, _
ByVal e As EventArgs)
dim i as integer
for i = 0 to txtBoxes.Length - 1
if txtBoxes(i).Focused then
dim txt as TextBox = CType(txtBoxes(i), TextBox)
if txt.Text.Length >= 5 then
txt.Select(0,5)
else
txt.Select(0,txt.Text.Length)
end if
end if
next
end sub
private sub mnuSelectAll_Click(ByVal sender As Object, _
ByVal e As EventArgs)
dim i as integer
for i = 0 to txtBoxes.Length - 1
if txtBoxes(i).Focused then
dim txt as TextBox = CType(txtBoxes(i), TextBox)
txt.SelectAll()
end if
next
end sub
private sub mnuScrollToCaret_Click(ByVal sender As Object, _
ByVal e As EventArgs)
dim i as integer
for i = 0 to txtBoxes.Length - 1
if txtBoxes(i).Focused then
dim txt as TextBox = CType(txtBoxes(i), TextBox)
txt.ScrollToCaret()
end if
next
end sub
private sub btn_Click(ByVal sender as object, _
ByVal e as EventArgs)
" Create a string array to hold the Lines property.
dim arLines(txtMulti.Lines.Length - 1) as string
arLines = txtMulti.Lines
" Use stringBuilder for efficiency.
dim str as string = "Line" + vbTab + "String" + vbCrLf
dim sb as new StringBuilder()
sb.Append(str)
" Iterate through the array & display each line.
dim i as integer
for i = 0 to arLines.Length - 1
str = i.ToString() + "." + vbTab + arLines(i) + vbCrLf
sb.Append(str)
next
txtDisplay.Text = sb.ToString()
end sub
end class
end namespace</source>
Convert input value in a TextField
<source lang="vbnet">Imports System.Windows.Forms <Global.Microsoft.VisualBasic.rupilerServices.DesignerGenerated()> _ Partial Class ConvertForm
Inherits System.Windows.Forms.Form
"Form overrides dispose to clean up the component list.
<System.Diagnostics.DebuggerNonUserCode()> _
Protected Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing AndAlso components IsNot Nothing Then
components.Dispose()
End If
MyBase.Dispose(disposing)
End Sub
"Required by the Windows Form Designer
Private components As System.ruponentModel.IContainer
"NOTE: The following procedure is required by the Windows Form Designer
"It can be modified using the Windows Form Designer.
"Do not modify it using the code editor.
<System.Diagnostics.DebuggerStepThrough()> _
Private Sub InitializeComponent()
Me.SourceFahrenheit = New System.Windows.Forms.RadioButton
Me.SourceCelsius = New System.Windows.Forms.RadioButton
Me.SourceKelvin = New System.Windows.Forms.RadioButton
Me.ValueFahrenheit = New System.Windows.Forms.TextBox
Me.ValueCelsius = New System.Windows.Forms.TextBox
Me.ValueKelvin = New System.Windows.Forms.TextBox
Me.ConvertTemperature = New System.Windows.Forms.Button
Me.SuspendLayout()
"
"SourceFahrenheit
"
Me.SourceFahrenheit.AutoSize = True
Me.SourceFahrenheit.Checked = True
Me.SourceFahrenheit.Location = New System.Drawing.Point(16, 24)
Me.SourceFahrenheit.Name = "SourceFahrenheit"
Me.SourceFahrenheit.Size = New System.Drawing.Size(75, 17)
Me.SourceFahrenheit.TabIndex = 0
Me.SourceFahrenheit.TabStop = True
Me.SourceFahrenheit.Text = "&Fahrenheit"
Me.SourceFahrenheit.UseVisualStyleBackColor = True
"
"SourceCelsius
"
Me.SourceCelsius.AutoSize = True
Me.SourceCelsius.Location = New System.Drawing.Point(16, 56)
Me.SourceCelsius.Name = "SourceCelsius"
Me.SourceCelsius.Size = New System.Drawing.Size(58, 17)
Me.SourceCelsius.TabIndex = 2
Me.SourceCelsius.Text = "&Celsius"
Me.SourceCelsius.UseVisualStyleBackColor = True
"
"SourceKelvin
"
Me.SourceKelvin.AutoSize = True
Me.SourceKelvin.Location = New System.Drawing.Point(16, 88)
Me.SourceKelvin.Name = "SourceKelvin"
Me.SourceKelvin.Size = New System.Drawing.Size(53, 17)
Me.SourceKelvin.TabIndex = 4
Me.SourceKelvin.Text = "&kelvin"
Me.SourceKelvin.UseVisualStyleBackColor = True
"
"ValueFahrenheit
"
Me.ValueFahrenheit.Location = New System.Drawing.Point(120, 24)
Me.ValueFahrenheit.Name = "ValueFahrenheit"
Me.ValueFahrenheit.Size = New System.Drawing.Size(100, 20)
Me.ValueFahrenheit.TabIndex = 1
"
"ValueCelsius
"
Me.ValueCelsius.Location = New System.Drawing.Point(120, 56)
Me.ValueCelsius.Name = "ValueCelsius"
Me.ValueCelsius.Size = New System.Drawing.Size(100, 20)
Me.ValueCelsius.TabIndex = 3
"
"ValueKelvin
"
Me.ValueKelvin.Location = New System.Drawing.Point(120, 88)
Me.ValueKelvin.Name = "ValueKelvin"
Me.ValueKelvin.Size = New System.Drawing.Size(100, 20)
Me.ValueKelvin.TabIndex = 5
"
"ConvertTemperature
"
Me.ConvertTemperature.Location = New System.Drawing.Point(144, 128)
Me.ConvertTemperature.Name = "ConvertTemperature"
Me.ConvertTemperature.Size = New System.Drawing.Size(75, 23)
Me.ConvertTemperature.TabIndex = 6
Me.ConvertTemperature.Text = "Convert"
Me.ConvertTemperature.UseVisualStyleBackColor = True
"
"ConvertForm
"
Me.AcceptButton = Me.ConvertTemperature
Me.AutoScaleDimensions = New System.Drawing.SizeF(6.0!, 13.0!)
Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font
Me.ClientSize = New System.Drawing.Size(245, 169)
Me.Controls.Add(Me.ConvertTemperature)
Me.Controls.Add(Me.ValueKelvin)
Me.Controls.Add(Me.ValueCelsius)
Me.Controls.Add(Me.ValueFahrenheit)
Me.Controls.Add(Me.SourceKelvin)
Me.Controls.Add(Me.SourceCelsius)
Me.Controls.Add(Me.SourceFahrenheit)
Me.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedSingle
Me.MaximizeBox = False
Me.MinimizeBox = False
Me.Name = "ConvertForm"
Me.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen
Me.Text = "Convert Temperatures"
Me.ResumeLayout(False)
Me.PerformLayout()
End Sub
Friend WithEvents SourceFahrenheit As System.Windows.Forms.RadioButton
Friend WithEvents SourceCelsius As System.Windows.Forms.RadioButton
Friend WithEvents SourceKelvin As System.Windows.Forms.RadioButton
Friend WithEvents ValueFahrenheit As System.Windows.Forms.TextBox
Friend WithEvents ValueCelsius As System.Windows.Forms.TextBox
Friend WithEvents ValueKelvin As System.Windows.Forms.TextBox
Friend WithEvents ConvertTemperature As System.Windows.Forms.Button
End Class Public Class ConvertForm
Private Sub ConvertTemperature_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ConvertTemperature.Click
On Error Resume Next
If (SourceFahrenheit.Checked = True) Then
If (IsNumeric(ValueFahrenheit.Text) = True) Then
ValueCelsius.Text = _
(Val(ValueFahrenheit.Text) - 32) / 1.8
ValueKelvin.Text = _
((Val(ValueFahrenheit.Text) - 32) / 1.8) + 273.15
Else
ValueCelsius.Text = "Error"
ValueKelvin.Text = "Error"
End If
ElseIf (SourceCelsius.Checked = True) Then
If (IsNumeric(ValueCelsius.Text) = True) Then
ValueFahrenheit.Text = _
(Val(ValueCelsius.Text) * 1.8) + 32
ValueKelvin.Text = Val(ValueCelsius.Text) + 273.15
Else
ValueFahrenheit.Text = "Error"
ValueKelvin.Text = "Error"
End If
Else
If (IsNumeric(ValueKelvin.Text) = True) Then
ValueFahrenheit.Text = _
((Val(ValueKelvin.Text) - 273.15) * 1.8) + 32
ValueCelsius.Text = Val(ValueKelvin.Text) - 273.15
Else
ValueFahrenheit.Text = "Error"
ValueCelsius.Text = "Error"
End If
End If
End Sub
End Class
public class FahrenheitCelsiusConverter
Public Shared Sub Main()
Application.Run(New ConvertForm)
End Sub
End Class</source>
Copy selection text from a TextBox and paste to another
<source lang="vbnet">Imports System.Drawing Imports System.Drawing.Drawing2D Imports System.Windows.Forms public class TextBoxCopyPaste
public Shared Sub Main
Application.Run(New Form1)
End Sub
End class Public Class Form1
Inherits System.Windows.Forms.Form
- Region " Windows Form Designer generated code "
Public Sub New()
MyBase.New()
"This call is required by the Windows Form Designer.
InitializeComponent()
"Add any initialization after the InitializeComponent() call
End Sub
"Form overrides dispose to clean up the component list.
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
"Required by the Windows Form Designer
Private components As System.ruponentModel.IContainer
"NOTE: The following procedure is required by the Windows Form Designer
"It can be modified using the Windows Form Designer.
"Do not modify it using the code editor.
Friend WithEvents TextBox1 As System.Windows.Forms.TextBox
Friend WithEvents Button1 As System.Windows.Forms.Button
Friend WithEvents Label1 As System.Windows.Forms.Label
Friend WithEvents TextBox2 As System.Windows.Forms.TextBox
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
Me.TextBox1 = New System.Windows.Forms.TextBox
Me.Button1 = New System.Windows.Forms.Button
Me.Label1 = New System.Windows.Forms.Label
Me.TextBox2 = New System.Windows.Forms.TextBox
Me.SuspendLayout()
"
"TextBox1
"
Me.TextBox1.Location = New System.Drawing.Point(128, 72)
Me.TextBox1.Name = "TextBox1"
Me.TextBox1.Size = New System.Drawing.Size(112, 20)
Me.TextBox1.TabIndex = 0
Me.TextBox1.Text = ""
"
"Button1
"
Me.Button1.Location = New System.Drawing.Point(128, 120)
Me.Button1.Name = "Button1"
Me.Button1.Size = New System.Drawing.Size(112, 23)
Me.Button1.TabIndex = 1
Me.Button1.Text = "Copy Selected Text"
"
"Label1
"
Me.Label1.Font = New System.Drawing.Font("Microsoft Sans Serif", 24.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
Me.Label1.Location = New System.Drawing.Point(0, 0)
Me.Label1.Name = "Label1"
Me.Label1.Size = New System.Drawing.Size(344, 48)
Me.Label1.TabIndex = 2
Me.Label1.Text = "Copying Selected Text"
"
"TextBox2
"
Me.TextBox2.Location = New System.Drawing.Point(128, 168)
Me.TextBox2.Name = "TextBox2"
Me.TextBox2.Size = New System.Drawing.Size(112, 20)
Me.TextBox2.TabIndex = 3
Me.TextBox2.Text = ""
"
"Form1
"
Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
Me.ClientSize = New System.Drawing.Size(360, 253)
Me.Controls.Add(Me.TextBox2)
Me.Controls.Add(Me.Label1)
Me.Controls.Add(Me.Button1)
Me.Controls.Add(Me.TextBox1)
Me.Name = "Form1"
Me.Text = "Form1"
Me.ResumeLayout(False)
End Sub
- End Region
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
TextBox1.Copy()
TextBox2.Paste()
End Sub
End Class</source>
Create PasswordField by setting the TextBox.PasswordChar
<source lang="vbnet">Imports System.Drawing Imports System.Drawing.Drawing2D Imports System.Windows.Forms public class PasswordFieldByTextBox
public Shared Sub Main
Application.Run(New Form1)
End Sub
End class Public Class Form1
Inherits System.Windows.Forms.Form
- Region " Windows Form Designer generated code "
Public Sub New()
MyBase.New()
"This call is required by the Windows Form Designer.
InitializeComponent()
"Add any initialization after the InitializeComponent() call
End Sub
"Form overrides dispose to clean up the component list.
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
"Required by the Windows Form Designer
Private components As System.ruponentModel.IContainer
"NOTE: The following procedure is required by the Windows Form Designer
"It can be modified using the Windows Form Designer.
"Do not modify it using the code editor.
Friend WithEvents TextBox1 As System.Windows.Forms.TextBox
Friend WithEvents Button1 As System.Windows.Forms.Button
Friend WithEvents TextBox2 As System.Windows.Forms.TextBox
Friend WithEvents Label1 As System.Windows.Forms.Label
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
Me.TextBox1 = New System.Windows.Forms.TextBox
Me.Button1 = New System.Windows.Forms.Button
Me.TextBox2 = New System.Windows.Forms.TextBox
Me.Label1 = New System.Windows.Forms.Label
Me.SuspendLayout()
"
"TextBox1
"
Me.TextBox1.Location = New System.Drawing.Point(96, 56)
Me.TextBox1.Name = "TextBox1"
Me.TextBox1.PasswordChar = Microsoft.VisualBasic.ChrW(42)
Me.TextBox1.TabIndex = 0
Me.TextBox1.Text = ""
"
"Button1
"
Me.Button1.Location = New System.Drawing.Point(104, 104)
Me.Button1.Name = "Button1"
Me.Button1.TabIndex = 1
Me.Button1.Text = "Read Text"
"
"TextBox2
"
Me.TextBox2.Location = New System.Drawing.Point(96, 160)
Me.TextBox2.Name = "TextBox2"
Me.TextBox2.TabIndex = 2
Me.TextBox2.Text = ""
"
"Label1
"
Me.Label1.Font = New System.Drawing.Font("Microsoft Sans Serif", 24.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
Me.Label1.Location = New System.Drawing.Point(0, 0)
Me.Label1.Name = "Label1"
Me.Label1.Size = New System.Drawing.Size(184, 40)
Me.Label1.TabIndex = 3
Me.Label1.Text = "Passwords"
"
"Form1
"
Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
Me.ClientSize = New System.Drawing.Size(292, 273)
Me.Controls.Add(Me.Label1)
Me.Controls.Add(Me.TextBox2)
Me.Controls.Add(Me.Button1)
Me.Controls.Add(Me.TextBox1)
Me.Name = "Form1"
Me.Text = "Form1"
Me.ResumeLayout(False)
End Sub
- End Region
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
TextBox2.Text = TextBox1.Text
End Sub
End Class</source>
Disable TextBox Context Menu
<source lang="vbnet">Imports System.Drawing Imports System.Drawing.Drawing2D Imports System.Windows.Forms public class DisableTextBoxContextMenu
public Shared Sub Main
Application.Run(New Form1)
End Sub
End class Public Class Form1
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim text_box As New NoCtxMnuTextBox
text_box.Location = New Point(TextBox1.Left, TextBox1.Top + TextBox1.Height + 4)
text_box.Size = TextBox1.Size
Me.Controls.Add(text_box)
End Sub
End Class Public Class NoCtxMnuTextBox
Inherits System.Windows.Forms.TextBox
Protected Overrides Sub WndProc(ByRef m As System.Windows.Forms.Message)
Const WM_CONTEXTMENU As Integer = &H7B
If m.Msg <> WM_CONTEXTMENU Then
MyBase.WndProc(m)
End If
End Sub
End Class <Global.Microsoft.VisualBasic.rupilerServices.DesignerGenerated()> _ Partial Public Class Form1
Inherits System.Windows.Forms.Form
"Form overrides dispose to clean up the component list.
<System.Diagnostics.DebuggerNonUserCode()> _
Protected Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing AndAlso components IsNot Nothing Then
components.Dispose()
End If
MyBase.Dispose(disposing)
End Sub
"Required by the Windows Form Designer
Private components As System.ruponentModel.IContainer
"NOTE: The following procedure is required by the Windows Form Designer
"It can be modified using the Windows Form Designer.
"Do not modify it using the code editor.
<System.Diagnostics.DebuggerStepThrough()> _
Private Sub InitializeComponent()
Me.TextBox1 = New System.Windows.Forms.TextBox
Me.SuspendLayout()
"
"TextBox1
"
Me.TextBox1.Location = New System.Drawing.Point(16, 16)
Me.TextBox1.Name = "TextBox1"
Me.TextBox1.Size = New System.Drawing.Size(120, 20)
Me.TextBox1.TabIndex = 0
"
"Form1
"
Me.AutoScaleDimensions = New System.Drawing.SizeF(6.0!, 13.0!)
Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font
Me.ClientSize = New System.Drawing.Size(156, 102)
Me.Controls.Add(Me.TextBox1)
Me.Name = "Form1"
Me.Text = "Form1"
Me.ResumeLayout(False)
Me.PerformLayout()
End Sub
Friend WithEvents TextBox1 As System.Windows.Forms.TextBox
End Class</source>
Display text file in a TextBox
<source lang="vbnet">Imports System.IO Imports System.Windows.Forms public class TextFileDisplayTextBox
public Shared Sub Main
Application.Run(New Form1)
End Sub
End class
Public Class Form1
Inherits System.Windows.Forms.Form
- Region " Windows Form Designer generated code "
Public Sub New()
MyBase.New()
"This call is required by the Windows Form Designer.
InitializeComponent()
"Add any initialization after the InitializeComponent() call
End Sub
"Form overrides dispose to clean up the component list.
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
"Required by the Windows Form Designer
Private components As System.ruponentModel.IContainer
"NOTE: The following procedure is required by the Windows Form Designer
"It can be modified using the Windows Form Designer.
"Do not modify it using the code editor.
Friend WithEvents Button1 As System.Windows.Forms.Button
Friend WithEvents TextBox1 As System.Windows.Forms.TextBox
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
Me.Button1 = New System.Windows.Forms.Button()
Me.TextBox1 = New System.Windows.Forms.TextBox()
Me.SuspendLayout()
"
"Button1
"
Me.Button1.Location = New System.Drawing.Point(104, 24)
Me.Button1.Name = "Button1"
Me.Button1.TabIndex = 0
Me.Button1.Text = "Select a File"
"
"TextBox1
"
Me.TextBox1.Location = New System.Drawing.Point(20, 80)
Me.TextBox1.Multiline = True
Me.TextBox1.Name = "TextBox1"
Me.TextBox1.Size = New System.Drawing.Size(250, 150)
Me.TextBox1.TabIndex = 1
Me.TextBox1.Text = ""
"
"Form1
"
Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
Me.ClientSize = New System.Drawing.Size(292, 273)
Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.Button1, Me.TextBox1})
Me.Name = "Form1"
Me.Text = "Form1"
Me.ResumeLayout(False)
End Sub
- End Region
Private Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim FileDB As New OpenFileDialog()
FileDB.Filter = "All files | *.* | Word files | *.doc | Text files | *.txt"
FileDB.FilterIndex = 3
FileDB.InitialDirectory = "C:\Temp"
If (FileDB.ShowDialog() = DialogResult.OK) Then
Dim FS As FileStream
Try
FS = FileDB.OpenFile()
Catch
MsgBox("Error opening " & FileDB.FileName)
End Try
Dim TextData(1025) As Byte
Dim BytesRead As Integer
Dim I As Integer
Dim NewText As String
Do
Try
BytesRead = FS.Read(TextData, 1, 1024)
NewText = ""
For I = 1 To BytesRead
NewText = NewText & Chr(TextData(I))
Next
TextBox1.AppendText(NewText)
Catch
MsgBox("Error reading file")
End Try
Loop While (BytesRead <> 0)
FS.Close()
Else
MsgBox("User selected Cancel")
End If
End Sub
End Class</source>
Get input from TextBox and Set to Label
<source lang="vbnet">Imports System.Drawing Imports System.Drawing.Drawing2D Imports System.Windows.Forms public class GetTextInTextBoxAndSetToLabel
public Shared Sub Main
Application.Run(New Form1)
End Sub
End class
Public Class Form1
Inherits System.Windows.Forms.Form
Public Sub New()
MyBase.New()
InitializeComponent()
End Sub
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
Private components As System.ruponentModel.IContainer
Friend WithEvents Label1 As System.Windows.Forms.Label
Friend WithEvents TextBox1 As System.Windows.Forms.TextBox
Friend WithEvents Button1 As System.Windows.Forms.Button
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
Me.Label1 = New System.Windows.Forms.Label
Me.TextBox1 = New System.Windows.Forms.TextBox
Me.Button1 = New System.Windows.Forms.Button
Me.SuspendLayout()
"
"Label1
"
Me.Label1.Location = New System.Drawing.Point(48, 16)
Me.Label1.Name = "Label1"
Me.Label1.Size = New System.Drawing.Size(160, 32)
Me.Label1.TabIndex = 0
"
"TextBox1
"
Me.TextBox1.Location = New System.Drawing.Point(64, 64)
Me.TextBox1.Name = "TextBox1"
Me.TextBox1.Size = New System.Drawing.Size(120, 20)
Me.TextBox1.TabIndex = 1
Me.TextBox1.Text = ""
"
"Button1
"
Me.Button1.Location = New System.Drawing.Point(88, 104)
Me.Button1.Name = "Button1"
Me.Button1.Size = New System.Drawing.Size(72, 24)
Me.Button1.TabIndex = 2
Me.Button1.Text = "Display"
"
"Form1
"
Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
Me.ClientSize = New System.Drawing.Size(256, 166)
Me.Controls.Add(Me.Button1)
Me.Controls.Add(Me.TextBox1)
Me.Controls.Add(Me.Label1)
Me.Name = "Form1"
Me.Text = "Form1"
Me.ResumeLayout(False)
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Label1.Text = "Hello," + TextBox1.Text + ""
End Sub
End Class</source>
Get selected text in TextBox
<source lang="vbnet">Imports System.Windows.Forms Imports System.Drawing.Text Imports System.Drawing Imports System.Drawing.Drawing2D public class TextBoxSelectionLength
public Shared Sub Main
Application.Run(New Form1)
End Sub
End class Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
If TextBox1.SelectionLength = 0 Then
MessageBox.Show(TextBox1.Text)
Else
MessageBox.Show(TextBox1.SelectedText)
End If
End Sub
End Class <Global.Microsoft.VisualBasic.rupilerServices.DesignerGenerated()> _ Partial Class Form1
Inherits System.Windows.Forms.Form
"Form overrides dispose to clean up the component list.
<System.Diagnostics.DebuggerNonUserCode()> _
Protected Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing AndAlso components IsNot Nothing Then
components.Dispose()
End If
MyBase.Dispose(disposing)
End Sub
"Required by the Windows Form Designer
Private components As System.ruponentModel.IContainer
"NOTE: The following procedure is required by the Windows Form Designer
"It can be modified using the Windows Form Designer.
"Do not modify it using the code editor.
<System.Diagnostics.DebuggerStepThrough()> _
Private Sub InitializeComponent()
Me.TextBox1 = New System.Windows.Forms.TextBox
Me.Button1 = New System.Windows.Forms.Button
Me.SuspendLayout()
"
"TextBox1
"
Me.TextBox1.Location = New System.Drawing.Point(12, 12)
Me.TextBox1.Multiline = True
Me.TextBox1.Name = "TextBox1"
Me.TextBox1.Size = New System.Drawing.Size(410, 137)
Me.TextBox1.TabIndex = 0
"
"Button1
"
Me.Button1.Location = New System.Drawing.Point(150, 173)
Me.Button1.Name = "Button1"
Me.Button1.Size = New System.Drawing.Size(131, 23)
Me.Button1.TabIndex = 1
Me.Button1.Text = "Display selected text"
Me.Button1.UseVisualStyleBackColor = True
"
"Form1
"
Me.AutoScaleDimensions = New System.Drawing.SizeF(6.0!, 12.0!)
Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font
Me.ClientSize = New System.Drawing.Size(434, 208)
Me.Controls.Add(Me.Button1)
Me.Controls.Add(Me.TextBox1)
Me.ResumeLayout(False)
Me.PerformLayout()
End Sub
Friend WithEvents TextBox1 As System.Windows.Forms.TextBox
Friend WithEvents Button1 As System.Windows.Forms.Button
End Class</source>
Inherit TextBox to create custom control based on TextBox
<source lang="vbnet">Imports System Imports System.Collections Imports System.IO Imports System.Windows.Forms Imports System.Drawing Imports System.Drawing.Drawing2D Public Class FileTextBox
Inherits TextBox
- Region " Component Designer generated code "
Public Sub New(ByVal Container As System.ruponentModel.IContainer)
MyClass.New()
"Required for Windows.Forms Class Composition Designer support
Container.Add(Me)
End Sub
Public Sub New()
MyBase.New()
"This call is required by the Component Designer.
InitializeComponent()
"Add any initialization after the InitializeComponent() call
End Sub
"Component overrides dispose to clean up the component list.
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
"Required by the Component Designer
Private components As System.ruponentModel.IContainer
"NOTE: The following procedure is required by the Component Designer
"It can be modified using the Component Designer.
"Do not modify it using the code editor.
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
components = New System.ruponentModel.Container()
End Sub
- End Region
Protected Overrides Sub OnTextChanged(ByVal e As System.EventArgs)
If Not File.Exists(Me.Text) Then
Me.ForeColor = Color.Red
Else
Me.ForeColor = Color.Black
End If
MyBase.OnTextChanged(e)
End Sub
End Class</source>
Multiline Text Boxes
<source lang="vbnet">Imports System.Drawing Imports System.Drawing.Drawing2D Imports System.Windows.Forms public class TextBoxMultiline
public Shared Sub Main
Application.Run(New Form1)
End Sub
End class Public Class Form1
Inherits System.Windows.Forms.Form
- Region " Windows Form Designer generated code "
Public Sub New()
MyBase.New()
"This call is required by the Windows Form Designer.
InitializeComponent()
"Add any initialization after the InitializeComponent() call
End Sub
"Form overrides dispose to clean up the component list.
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
"Required by the Windows Form Designer
Private components As System.ruponentModel.IContainer
"NOTE: The following procedure is required by the Windows Form Designer
"It can be modified using the Windows Form Designer.
"Do not modify it using the code editor.
Friend WithEvents Label1 As System.Windows.Forms.Label
Friend WithEvents TextBox1 As System.Windows.Forms.TextBox
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
Me.Label1 = New System.Windows.Forms.Label
Me.TextBox1 = New System.Windows.Forms.TextBox
Me.SuspendLayout()
"
"TextBox1
"
Me.TextBox1.Location = New System.Drawing.Point(5, 5)
Me.TextBox1.Multiline = True
Me.TextBox1.Name = "TextBox1"
Me.TextBox1.ScrollBars = System.Windows.Forms.ScrollBars.Both
Me.TextBox1.Size = New System.Drawing.Size(200, 150)
Me.TextBox1.TabIndex = 2
Me.TextBox1.Text = ""
"
"Form1
"
Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
Me.ClientSize = New System.Drawing.Size(288, 189)
Me.Controls.Add(Me.TextBox1)
Me.Controls.Add(Me.Label1)
Me.Name = "Form1"
Me.Text = "Form1"
Me.ResumeLayout(False)
End Sub
- End Region
End Class</source>
Numeric TextBox
<source lang="vbnet">Imports System.Windows.Forms public class NumericTextBoxDemo
public Shared Sub Main
Application.Run(New Form1)
End Sub
End class Public Class Form1
Inherits System.Windows.Forms.Form
- Region " Windows Form Designer generated code "
Public Sub New()
MyBase.New()
"This call is required by the Windows Form Designer.
InitializeComponent()
"Add any initialization after the InitializeComponent() call
End Sub
"Form overrides dispose to clean up the component list.
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
"Required by the Windows Form Designer
Private components As System.ruponentModel.IContainer
"NOTE: The following procedure is required by the Windows Form Designer
"It can be modified using the Windows Form Designer.
"Do not modify it using the code editor.
Friend WithEvents Button1 As System.Windows.Forms.Button
Friend WithEvents NumTextBox1 As NumTextBox
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
Me.Button1 = New System.Windows.Forms.Button()
Me.NumTextBox1 = New NumTextBox()
Me.SuspendLayout()
"
"Button1
"
Me.Button1.Location = New System.Drawing.Point(144, 120)
Me.Button1.Name = "Button1"
Me.Button1.TabIndex = 1
Me.Button1.Text = "Do It!"
"
"NumTextBox1
"
Me.NumTextBox1.Location = New System.Drawing.Point(32, 56)
Me.NumTextBox1.Name = "NumTextBox1"
Me.NumTextBox1.TabIndex = 3
Me.NumTextBox1.Text = "NumTextBox1"
"
"Form1
"
Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
Me.ClientSize = New System.Drawing.Size(292, 266)
Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.NumTextBox1, Me.Button1})
Me.Name = "Form1"
Me.Text = "Form1"
Me.ResumeLayout(False)
End Sub
- End Region
End Class
Public Class NumTextBox
Inherits System.Windows.Forms.TextBox
- Region " Windows Form Designer generated code "
Public Sub New()
MyBase.New()
"This call is required by the Windows Form Designer.
InitializeComponent()
"Add any initialization after the InitializeComponent() call
End Sub
"UserControl1 overrides dispose to clean up the component list.
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
"Required by the Windows Form Designer
Private components As System.ruponentModel.IContainer
"NOTE: The following procedure is required by the Windows Form Designer
"It can be modified using the Windows Form Designer.
"Do not modify it using the code editor.
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
"
"NumTextBox
"
End Sub
- End Region
Protected Overrides Sub OnLeave(ByVal e As System.EventArgs)
If Not IsNumeric(Me.Text) Then
MessageBox.Show("You must enter a numeric value!", _
"Please try again....", MessageBoxButtons.OK, _
MessageBoxIcon.Exclamation)
Me.Focus()
End If
MyBase.OnLeave(e)
End Sub
End Class</source>
Save text in TextBox to a file
<source lang="vbnet">Imports System.IO Imports System.Windows.Forms public class SaveTextBoxToFile
public Shared Sub Main
Application.Run(New Form1)
End Sub
End class Public Class Form1
Inherits System.Windows.Forms.Form
- Region " Windows Form Designer generated code "
Public Sub New()
MyBase.New()
"This call is required by the Windows Form Designer.
InitializeComponent()
"Add any initialization after the InitializeComponent() call
End Sub
"Form overrides dispose to clean up the component list.
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
"Required by the Windows Form Designer
Private components As System.ruponentModel.IContainer
"NOTE: The following procedure is required by the Windows Form Designer
"It can be modified using the Windows Form Designer.
"Do not modify it using the code editor.
Friend WithEvents Button1 As System.Windows.Forms.Button
Friend WithEvents TextBox1 As System.Windows.Forms.TextBox
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
Me.Button1 = New System.Windows.Forms.Button()
Me.TextBox1 = New System.Windows.Forms.TextBox()
Me.SuspendLayout()
"
"Button1
"
Me.Button1.Location = New System.Drawing.Point(104, 24)
Me.Button1.Name = "Button1"
Me.Button1.TabIndex = 0
Me.Button1.Text = "Save to File"
"
"TextBox1
"
Me.TextBox1.Location = New System.Drawing.Point(20, 80)
Me.TextBox1.Multiline = True
Me.TextBox1.Name = "TextBox1"
Me.TextBox1.Size = New System.Drawing.Size(250, 150)
Me.TextBox1.TabIndex = 1
Me.TextBox1.Text = ""
"
"Form1
"
Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
Me.ClientSize = New System.Drawing.Size(292, 273)
Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.Button1, Me.TextBox1})
Me.Name = "Form1"
Me.Text = "SaveTextToFile"
Me.ResumeLayout(False)
End Sub
- End Region
Private Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim FileDB As New SaveFileDialog()
FileDB.Filter = "All files | *.* | Word files | *.doc | Text files | *.txt"
FileDB.FilterIndex = 3
FileDB.InitialDirectory = "C:\Temp"
FileDB.AddExtension = True
FileDB.DefaultExt = "txt"
If (FileDB.ShowDialog() = DialogResult.OK) Then
Dim FS As FileStream
Try
FS = New FileStream(FileDB.FileName, FileMode.Create)
Dim I As Integer
For I = 0 To TextBox1.Text.Length - 1
FS.WriteByte(Asc(TextBox1.Text.Chars(I)))
Next
Catch
Console.WriteLine("Error writing file")
End Try
FS.Close()
MsgBox("Text saved to " & FileDB.FileName)
Else
MsgBox("User selected Cancel")
End If
End Sub
End Class</source>
TextBox Text Changed Event
<source lang="vbnet">imports System imports System.Drawing imports System.Windows.Forms public class TextBoxTextChanged : inherits Form
dim txt as TextBox
dim btn as Button
dim strOriginal as string
public sub New()
Text = "TextBox Modified and TextChanged"
Size = new Size(300, 375)
txt = new TextBox()
txt.Parent = me
txt.Text = "Enter text here."
txt.Size = new Size(280, 275)
txt.Location = new Point(10,10)
AddHandler txt.TextChanged, AddressOf txt_TextChanged
txt.Multiline = true
txt.BorderStyle = BorderStyle.Fixed3D
txt.ScrollBars = ScrollBars.Vertical
txt.Anchor = AnchorStyles.Left or AnchorStyles.Right or AnchorStyles.Top or AnchorStyles.Bottom
strOriginal = txt.Text
btn = new Button()
btn.Parent = me
btn.Text = "Check "
btn.Location = new Point(20,320)
AddHandler btn.Click, AddressOf btn_Click
btn.Anchor = AnchorStyles.Bottom
end sub
public shared sub Main()
Application.Run(new TextBoxTextChanged())
end sub
private sub txt_TextChanged(ByVal sender as object,ByVal e as EventArgs)
Console.WriteLine("txt_TextChanged")
if strOriginal = txt.Text then
txt.Modified = false
else
txt.Modified = true
end if
end sub
private sub btn_Click(ByVal sender as object,ByVal e as EventArgs)
if txt.Modified then
Console.WriteLine("modified.")
strOriginal = txt.Text
txt.Modified = false
else
Console.WriteLine("not been modified." )
end if
end sub
end class</source>
