VB.Net/Database ADO.net/Table Schema

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Get data table schema form SqlDataReader

<source lang="vbnet"> Imports System Imports System.Data Imports System.Data.SqlClient

public class MainClass

  Shared Sub Main()
     Dim thisConnection As New SqlConnection("server=(local)\SQLEXPRESS;" & _
         "integrated security=sspi;database=MyDatabase")
     Dim sql As String = "SELECT * FROM Employee"
     Dim thisCommand As New SqlCommand(sql, thisConnection)
     Try
        thisConnection.Open()
        Console.WriteLine("Connection Opened")
        Dim thisReader As SqlDataReader = thisCommand.ExecuteReader()
        Dim schema As DataTable = thisReader.GetSchemaTable()
        For Each row As DataRow In schema.Rows
           For Each col As DataColumn In schema.Columns
              Console.WriteLine(col.ColumnName & " = " & row(col).ToString())
           Next
           Console.WriteLine("---------------")
        Next
        thisReader.Close()
     Catch ex As SqlException
        Console.WriteLine("Error: " & ex.ToString())
     Finally
        thisConnection.Close()
        Console.WriteLine("Connection Closed")
     End Try
  End Sub

End Class

      </source>


Use datagrid to display table schema

<source lang="vbnet"> 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

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
  1. 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 DataGrid1 As System.Windows.Forms.DataGrid
   <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
       Me.Button1 = New System.Windows.Forms.Button()
       Me.DataGrid1 = New System.Windows.Forms.DataGrid()
       CType(Me.DataGrid1, System.ruponentModel.ISupportInitialize).BeginInit()
       Me.SuspendLayout()
       "
       "Button1
       "
       Me.Button1.Location = New System.Drawing.Point(648, 448)
       Me.Button1.Name = "Button1"
       Me.Button1.TabIndex = 3
       Me.Button1.Text = "Go"
       "
       "DataGrid1
       "
       Me.DataGrid1.DataMember = ""
       Me.DataGrid1.HeaderForeColor = System.Drawing.SystemColors.ControlText
       Me.DataGrid1.Location = New System.Drawing.Point(8, 8)
       Me.DataGrid1.Name = "DataGrid1"
       Me.DataGrid1.Size = New System.Drawing.Size(720, 432)
       Me.DataGrid1.TabIndex = 2
       "
       "Form1
       "
       Me.AutoScaleBaseSize = New System.Drawing.Size(6, 15)
       Me.ClientSize = New System.Drawing.Size(736, 480)
       Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.Button1, Me.DataGrid1})
       Me.Name = "Form1"
       Me.Text = "Form1"
       CType(Me.DataGrid1, System.ruponentModel.ISupportInitialize).EndInit()
       Me.ResumeLayout(False)
   End Sub
  1. End Region
   Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
       Dim con As New SqlConnection( _
           "Server=(local)\SQLEXPRESS;Initial Catalog=MyDatabase;Integrated Security=SSPI")
       Dim cmd As New SqlCommand("SELECT * FROM Employee", con)
       Try
           con.Open()
           Dim reader As SqlDataReader = _
                                 cmd.ExecuteReader(CommandBehavior.SchemaOnly)
           DataGrid1.SetDataBinding(reader.GetSchemaTable(), "")
           reader.Close()
       Finally
           con.Close()
       End Try
   End Sub

End Class

      </source>