VB.Net/Database ADO.net/OleDb Table Schema

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Use OleDb to get the data table schema

Imports System
Imports System.Collections
Imports System.Data
Imports System.IO
Imports System.Xml.Serialization
Imports System.Xml
Imports System.Windows.Forms
Imports System.Data.SqlClient
Imports System.Data.OleDb
Public Class MainClass
    Shared Sub Main()
        Dim form1 As Form = New Form1
        Application.Run(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 SchemaTableList As System.Windows.Forms.ListView
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.Button1 = New System.Windows.Forms.Button()
        Me.SchemaTableList = New System.Windows.Forms.ListView()
        Me.SuspendLayout()
        "
        "Button1
        "
        Me.Button1.Location = New System.Drawing.Point(808, 520)
        Me.Button1.Name = "Button1"
        Me.Button1.Size = New System.Drawing.Size(136, 23)
        Me.Button1.TabIndex = 3
        Me.Button1.Text = "Read Schema"
        "
        "SchemaTableList
        "
        Me.SchemaTableList.Dock = System.Windows.Forms.DockStyle.Top
        Me.SchemaTableList.Name = "SchemaTableList"
        Me.SchemaTableList.Size = New System.Drawing.Size(952, 512)
        Me.SchemaTableList.TabIndex = 2
        "
        "Form1
        "
        Me.AutoScaleBaseSize = New System.Drawing.Size(6, 15)
        Me.ClientSize = New System.Drawing.Size(952, 552)
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.Button1, Me.SchemaTableList})
        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
        Dim conn As OleDbConnection = New OleDbConnection _
            ("Provider=SQLOLEDB;Data Source=(local)\SQLEXPRESS;Initial Catalog=MyDatabase;uid=sa;pwd=vbex;")
        " Retrieving schema for columns from a single table
        Dim cmd As OleDbCommand = New OleDbCommand("Employee", conn)
        cmd.rumandType = CommandType.TableDirect
        " Retrieve schema only
        conn.Open()
        Dim reader As OleDbDataReader = cmd.ExecuteReader(CommandBehavior.SchemaOnly)
        " Get references to schema information
        Dim SchemaTable As DataTable = reader.GetSchemaTable()
        " Close and release the connection before processing results
        reader.Close()
        conn.Close()
        " Display schema table column headers
        Dim col As DataColumn
        SchemaTableList.View = View.Details
        For Each col In SchemaTable.Columns
            SchemaTableList.Columns.Add(col.ColumnName, 100, HorizontalAlignment.Left)
        Next
        " Display schema
        Dim row As DataRow
        Dim ColCount As Integer = SchemaTable.Columns.Count
        For Each row In SchemaTable.Rows
            Dim OrderDetails(ColCount) As String
            Dim ColIdx As Integer
            For ColIdx = 0 To ColCount - 1
                OrderDetails(ColIdx) = Convert.ToString(row(ColIdx))
            Next
            Dim NewItem As ListViewItem = New ListViewItem(OrderDetails)
            SchemaTableList.Items.Add(NewItem)
        Next
    End Sub
End Class


Use OleDb to get the data table schema and display in a DataGrid

Imports System
Imports System.Collections
Imports System.Data
Imports System.IO
Imports System.Xml.Serialization
Imports System.Xml
Imports System.Windows.Forms
Imports System.Data.SqlClient
Imports System.Data.OleDb
Public Class MainClass
    Shared Sub Main()
        Dim form1 As Form = New Form1
        Application.Run(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 SchemaTableList As System.Windows.Forms.ListView
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.Button1 = New System.Windows.Forms.Button()
        Me.SchemaTableList = New System.Windows.Forms.ListView()
        Me.SuspendLayout()
        "
        "Button1
        "
        Me.Button1.Location = New System.Drawing.Point(808, 520)
        Me.Button1.Name = "Button1"
        Me.Button1.Size = New System.Drawing.Size(136, 23)
        Me.Button1.TabIndex = 3
        Me.Button1.Text = "Read Schema"
        "
        "SchemaTableList
        "
        Me.SchemaTableList.Dock = System.Windows.Forms.DockStyle.Top
        Me.SchemaTableList.Name = "SchemaTableList"
        Me.SchemaTableList.Size = New System.Drawing.Size(952, 512)
        Me.SchemaTableList.TabIndex = 2
        "
        "Form1
        "
        Me.AutoScaleBaseSize = New System.Drawing.Size(6, 15)
        Me.ClientSize = New System.Drawing.Size(952, 552)
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.Button1, Me.SchemaTableList})
        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
        Dim conn As OleDbConnection = New OleDbConnection _
            ("Provider=SQLOLEDB;Data Source=(local)\SQLEXPRESS;Initial Catalog=MyDatabase;uid=sa;pwd=vbex;")
        " Retrieving schema for columns from a single table
        Dim cmd As OleDbCommand = New OleDbCommand("Employee", conn)
        cmd.rumandType = CommandType.TableDirect
        " Retrieve schema only
        conn.Open()
        Dim reader As OleDbDataReader = cmd.ExecuteReader(CommandBehavior.SchemaOnly)
        " Get references to schema information
        Dim SchemaTable As DataTable = reader.GetSchemaTable()
        " Close and release the connection before processing results
        reader.Close()
        conn.Close()
        " Display schema table column headers
        Dim col As DataColumn
        SchemaTableList.View = View.Details
        For Each col In SchemaTable.Columns
            SchemaTableList.Columns.Add(col.ColumnName, 100, HorizontalAlignment.Left)
        Next
        " Display schema
        Dim row As DataRow
        Dim ColCount As Integer = SchemaTable.Columns.Count
        For Each row In SchemaTable.Rows
            Dim OrderDetails(ColCount) As String
            Dim ColIdx As Integer
            For ColIdx = 0 To ColCount - 1
                OrderDetails(ColIdx) = Convert.ToString(row(ColIdx))
            Next
            Dim NewItem As ListViewItem = New ListViewItem(OrderDetails)
            SchemaTableList.Items.Add(NewItem)
        Next
    End Sub
End Class
Источник — «http://vbex.ru/index.php?title=VB.Net/Database_ADO.net/OleDb_Table_Schema&oldid=663»