在.net中调用存储过程的另一种方法

‘////////////////////////////////////////////////////////////////////////////////////

CREATE PROCEDURE Test_procedure @cid int ,@y int, @n varchar(10) output

AS

select * from city where cid=@cid

if @y=1

begin

  set @n = '成功！'

  return 0

end

else

begin

  set @n = '失败！'

  return -1

end

GO

[程序中调用存储过程]

‘////////////////////////////////////////////////////////////////////////////////////

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        Dim conn As OleDbConnection

        Try

            conn = New OleDbConnection("provider=sqloledb;data source=localhost;user id=sa;password=;initial catalog=jiang")

            Dim cmd As New OleDbCommand(" {? = call Test_procedure(?,?,?)}", conn)

            conn.Open()

            With cmd

                .CommandType = CommandType.Text ‘这句可以省略，因为是默认设置，但这里还是显式地写出以引起注意

                .Parameters.Add("@retval", OleDbType.Integer)

                .Parameters.Add("@cid", OleDbType.Integer)

                .Parameters.Add("@y", OleDbType.Integer)

                .Parameters.Add("@n", OleDbType.VarChar, 10)

                .Parameters("@n").Direction = ParameterDirection.Output

                .Parameters("@retval").Direction = ParameterDirection.ReturnValue

                .Parameters("@cid").Value = 1

                .Parameters("@y").Value = 1

                .ExecuteNonQuery()

                MessageBox.Show(.Parameters("@n").Value) ‘测试结果为“成功！”

            End With

        Catch ex As Exception

            MessageBox.Show(ex.ToString)

       Finally

            conn.Close()

        End Try

    End Sub