VB.Net/GUI/ComboBox

Get selected Item from ComboBox

Imports System.Windows.Forms

Module Module1
    Sub Main()
        Application.Run(New Form1)
    End Sub
End Module


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 ComboBox1 As System.Windows.Forms.ruboBox
    Friend WithEvents Button1 As System.Windows.Forms.Button
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.ruboBox1 = New System.Windows.Forms.ruboBox()
        Me.Button1 = New System.Windows.Forms.Button()
        Me.SuspendLayout()
        "
        "ComboBox1
        "
        Me.ruboBox1.Items.AddRange(New Object() {"A", "B", "C", "D", "E"})
        Me.ruboBox1.Location = New System.Drawing.Point(32, 32)
        Me.ruboBox1.Name = "ComboBox1"
        Me.ruboBox1.Size = New System.Drawing.Size(136, 21)
        Me.ruboBox1.TabIndex = 0
        Me.ruboBox1.Text = "A"
        "
        "Button1
        "
        Me.Button1.Location = New System.Drawing.Point(128, 112)
        Me.Button1.Name = "Button1"
        Me.Button1.TabIndex = 1
        Me.Button1.Text = "Done"
        "
        "Form1
        "
        Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
        Me.ClientSize = New System.Drawing.Size(328, 173)
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.Button1, Me.ruboBox1})
        Me.Name = "Form1"
        Me.Text = "ComboBoxDemo"
        Me.ResumeLayout(False)
    End Sub
#End Region
    Private Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
        If (ComboBox1.SelectedItem <> "") Then
            MessageBox.Show("You selected: " & ComboBox1.SelectedItem)
        Else
            MessageBox.Show("You must select an item")
        End If
    End Sub
End Class

Using ComboBox to select shape to draw

Imports System
Imports System.Drawing
Imports System.Windows.Forms
Public Class MainClass
   Shared Sub Main()
        Dim myform As Form = New FrmComboBox()
        Application.Run(myform)
   End Sub " Main
End Class
Public Class FrmComboBox
   Inherits 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
   Friend WithEvents cboImage As System.Windows.Forms.ruboBox
   "Required by the Windows Form Designer
   Private components As System.ruponentModel.Container
   "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.cboImage = New System.Windows.Forms.ruboBox()
      Me.SuspendLayout()
      "
      "cboImage
      "
      Me.cboImage.DropDownWidth = 121
      Me.cboImage.Items.AddRange(New Object() {"Circle", "Square", "Ellipse", "Pie", "Filled Circle", "Filled Square", "Filled Ellipse", "Filled Pie"})
      Me.cboImage.Location = New System.Drawing.Point(24, 16)
      Me.cboImage.Name = "cboImage"
      Me.cboImage.Size = New System.Drawing.Size(121, 21)
      Me.cboImage.TabIndex = 0
      "
      "FrmComboBox
      "
      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.cboImage})
      Me.Name = "FrmComboBox"
      Me.Text = "ComboBoxTest"
      Me.ResumeLayout(False)
   End Sub
#End Region
   Private Sub cboImage_SelectedIndexChanged _
      (ByVal sender As System.Object, _
      ByVal e As System.EventArgs) _
      Handles cboImage.SelectedIndexChanged
      Dim myGraphics As Graphics = MyBase.CreateGraphics()
      Dim myPen As New Pen(Color.Red)
      Dim mySolidBrush As New SolidBrush(Color.Red)
      Dim x As Integer
      Dim y As Integer
      Dim width As Integer
      Dim height As Integer
      
      x = 50
      y = 50
      width = 150
      height = 150
      myGraphics.Clear(Color.Black)
      Select Case cboImage.SelectedIndex
         Case 0 
            myGraphics.DrawEllipse(myPen, x, y, width, height)
         Case 1 
            myGraphics.DrawRectangle(myPen, x, y, width, height)
         Case 2 
            myGraphics.DrawEllipse(myPen, x, y, width, 75)
         Case 3 
            myGraphics.DrawPie(myPen, x, y, width, height, 0, 45)
         Case 4 
            myGraphics.FillEllipse(mySolidBrush, x, y, width, height)
         Case 5 
            myGraphics.FillRectangle(mySolidBrush, x, y, width, height)
         Case 6 
            myGraphics.FillEllipse(mySolidBrush, 50, 85, 150, 115)
         Case 7 
            myGraphics.FillPie(mySolidBrush, 50, 50, 150, 150, 0, 45)
      End Select
   End Sub
End Class