VB.Net/Database ADO.net/SqlCommand Create — различия между версиями

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Версия 16:40, 26 мая 2010

A method to handle asynchronous completion using callbacks.

  
Imports System
Imports System.Data
Imports System.Threading
Imports System.Data.SqlClient
    Public Class MainClass
        
        Public Shared Sub CallBackHandler(ByVal result As IAsyncResult)
            Using cmd As SqlCommand = TryCast(result.AsyncState, SqlCommand)
                Using reader As SqlDataReader = cmd.EndExecuteReader(result)
                    SyncLock Console.Out
                        While reader.Read
                            Console.WriteLine("{0}   {1}   {2}   {3}", reader("ComponentID"), reader("ComponentDesc"), reader("TotalQuantity"), reader("ListPrice"))
                        End While
                    End SyncLock
                End Using
            End Using
        End Sub
        Public Shared Sub Main()
            Using con As New SqlConnection
                con.ConnectionString = "Data Source=.\sqlexpress;Database=AdventureWorks;Integrated Security=SSPI;Asynchronous Processing=true;"
                Using cmd As SqlCommand = con.CreateCommand
                    cmd.rumandType = CommandType.StoredProcedure
                    cmd.rumandText = "uspGetBillingInfo"
                    cmd.Parameters.Add("@StartProductID", SqlDbType.Int).Value = 771
                    cmd.Parameters.Add("@CheckDate", SqlDbType.DateTime).Value = DateTime.Parse("07/10/2000")
                    con.Open()
                    cmd.BeginExecuteReader(AddressOf CallBackHandler, cmd)
                End Using
                con.Close()
            End Using
        End Sub
    End Class


Create a Database through SqlConnection

 
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")
      "Create Command object
      Dim nonqueryCommand As SqlCommand = thisConnection.CreateCommand()
      Try
         " Open Connection
         thisConnection.Open()
         Console.WriteLine("Connection Opened")
         " Execute NonQuery To Create Database
         nonqueryCommand.rumandText = "CREATE DATABASE MyDb"
         Console.WriteLine("Executing {0}",nonqueryCommand.rumandText)
         Console.WriteLine("Number of rows affected : {0}",nonqueryCommand.ExecuteNonQuery())

         " Execute NonQuery To Drop Database
         nonqueryCommand.rumandText = "Drop DATABASE MyDb"
         Console.WriteLine("Executing {0}",nonqueryCommand.rumandText)
         Console.WriteLine("Number of rows affected : {0}",nonqueryCommand.ExecuteNonQuery())

      Catch ex As SqlException
         " Display error
         Console.WriteLine("Error: " & ex.ToString())
      Finally
         " Close Connection
         thisConnection.Close()
         Console.WriteLine("Connection Closed")
      End Try
   End Sub
End Class


Execute NonQuery To Create Table and report how many rows affected

 
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=tempdb")
      "Create Command object
      Dim nonqueryCommand As SqlCommand = thisConnection.CreateCommand()
      Try
         " Open Connection
         thisConnection.Open()
         Console.WriteLine("Connection Opened")

         " Execute NonQuery To Create Table
         nonqueryCommand.rumandText = "CREATE TABLE MyTable (ID integer)"
         Console.WriteLine("Executing {0}", nonqueryCommand.rumandText)
         Console.WriteLine("Number of rows affected : {0}", nonqueryCommand.ExecuteNonQuery())
         " Execute NonQuery To Drop Table
         nonqueryCommand.rumandText = "DROP TABLE MyTable"
         Console.WriteLine("Executing {0}", nonqueryCommand.rumandText)
         Console.WriteLine("Number of rows affected : {0}", nonqueryCommand.ExecuteNonQuery())
      Catch ex As SqlException
         " Display error
         Console.WriteLine("Error: " & ex.ToString())
      Finally
         " Close Connection
         thisConnection.Close()
         Console.WriteLine("Connection Closed")
      End Try
   End Sub
End Class