VB.Net by API/System.Data.SqlClient/SqlDataReader

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SqlDataReader.GetOrdinal

<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 Dim WithEvents con As SqlConnection
   Shared Sub Main()
       con = New SqlConnection("Server=(local)\SQLEXPRESS;Initial Catalog=MyDatabase;Integrated Security=SSPI") 
       Dim cmd As New SqlCommand()
       cmd.rumandText = "SELECT * FROM Employee"
       cmd.Connection = con
       Try
           con.Open()
           Dim reader As SqlDataReader = cmd.ExecuteReader()
           Dim OrderIDIdx As Integer = reader.GetOrdinal("ID")
           "Dim OrderDateIdx As Integer = reader.GetOrdinal("FirstName")
           "Dim OrderFreightIdx As Integer = reader.GetOrdinal("LastName")
           Do
               While reader.Read()
                   Dim OrderID As Integer = reader.GetInt32(OrderIDIdx)
                   "Dim OrderDate As DateTime = reader.GetDateTime(OrderDateIdx)
                   "Dim OrderFreight As Decimal = reader.GetDecimal(OrderFreightIdx)
                   "Console.WriteLine(OrderID & vbTab & OrderDate & vbTab & OrderFreight)
                   Console.WriteLine(OrderID & vbTab )
               End While
           Loop While reader.NextResult()
           reader.Close()
       Finally
           con.Close()
       End Try
   End Sub

End Class


 </source>


SqlDataReader.GetSchemaTable()

<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
        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>


SqlDataReader.GetString

<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 Dim WithEvents con As SqlConnection
   Shared Sub Main()
       con = New SqlConnection("Server=(local)\SQLEXPRESS;Initial Catalog=MyDatabase;Integrated Security=SSPI") 
       Dim cmd As New SqlCommand()
       cmd.rumandText = "SELECT FirstName, LastName FROM Employee"
       cmd.Connection = con
       Try
           con.Open()
           Dim reader As SqlDataReader = cmd.ExecuteReader(CommandBehavior.SingleRow)
           While reader.Read()
               Console.WriteLine("{0} - {1}", _
                               reader.GetString(0), reader.GetString(1))
           End While
           reader.Close()
       Finally
           con.Close()
       End Try
   End Sub

End Class


 </source>


SqlDataReader.NextResult()

<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 Dim WithEvents con As SqlConnection
   Shared Sub Main()
       con = New SqlConnection("Server=(local)\SQLEXPRESS;Initial Catalog=MyDatabase;Integrated Security=SSPI") 
       Dim cmd As New SqlCommand()
       cmd.rumandText = "SELECT * FROM Employee; SELECT * FROM Employee"
       cmd.Connection = con
       Try
           con.Open()
           Dim reader As SqlDataReader = cmd.ExecuteReader()
           Do
               While reader.Read()
                   Console.WriteLine(reader(0) & vbTab & reader(1))
               End While
           Loop While reader.NextResult()
           reader.Close()
       Finally
           con.Close()
       End Try
   End Sub

End Class


 </source>


SqlDataReader.Read()

<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 Dim WithEvents con As SqlConnection
   Shared Sub Main()
       con = New SqlConnection("Server=(local)\SQLEXPRESS;Initial Catalog=MyDatabase;Integrated Security=SSPI") 
       Dim cmd As New SqlCommand()
       cmd.rumandText = "SELECT FirstName, LastName FROM Employee"
       cmd.Connection = con
       Try
           con.Open()
           Dim reader As SqlDataReader = cmd.ExecuteReader(CommandBehavior.SingleRow)
           While reader.Read()
               Console.WriteLine("{0} - {1}", _
                               reader.GetString(0), reader.GetString(1))
           End While
           reader.Close()
       Finally
           con.Close()
       End Try
   End Sub

End Class


 </source>