存储过程 VB.NET MYSQL
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/25375919/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Stored Procedures VB.NET MYSQL
提问by Bryan
Hello I still having problems, it brings me DBnull and I tried the Store procedure and works. This is my code. If someone could help me I will appreciate.
您好，我仍然遇到问题，它给我带来了 DBnull，我尝试了 Store 过程并且可以正常工作。这是我的代码。如果有人可以帮助我，我将不胜感激。
conexion.Open()
command.Connection = conexion
command.CommandText = "TraerPaisOrigen"
command.CommandType = CommandType.StoredProcedure
command.Parameters.AddWithValue("@Cod_Dua", TxtCodDUA.Text)
command.Parameters("@Cod_Dua").Direction = ParameterDirection.Input
command.Parameters.AddWithValue("@_PaisOrigen", MySqlDbType.VarChar)
command.Parameters("@_PaisOrigen").Direction = ParameterDirection.Output
command.ExecuteNonQuery()
'XML_PaisOrigen is a String
XML_PaisOrigen = command.Parameters(0).Value.ToString
conexion.Close()
My Store Procedured
我的商店程序
CREATE PROCEDURE TraerPaisOrigen( IN Cod_Dua INT, OUT _PaisOrigen VARCHAR(2))
采纳答案by jmcilhinney
This:
这个：
command.Parameters.AddWithValue("@Cod_Dua", TxtCodDUA.Text)
command.Parameters("@Cod_Dua").Direction = ParameterDirection.Input
should be this:
应该是这样的：
command.Parameters.AddWithValue("@Cod_Dua", CInt(TxtCodDUA.Text))
This:
这个：
command.Parameters.AddWithValue("@_PaisOrigen", MySqlDbType.VarChar)
command.Parameters("@_PaisOrigen").Direction = ParameterDirection.Output
should be this:
应该是这样的：
command.Parameters.Add("@_PaisOrigen", MySqlDbType.VarChar, 2).Direction = ParameterDirection.Output
This:
这个：
XML_PaisOrigen = command.Parameters(0).Value.ToString
should be this:
应该是这样的：
XML_PaisOrigen = command.Parameters(1).Value.ToString()
回答by Bryan
Try
conexion.Open()
command.Connection = conexion
command.CommandText = "TraerPaisOrigen"
command.CommandType = CommandType.StoredProcedure
command.Parameters.AddWithValue("@Cod_Dua", CInt(TxtCodDUA.Text))
command.Parameters("@Cod_Dua").Direction = ParameterDirection.Input
command.Parameters.Add("@_PaisOrigen", MySqlDbType.VarChar, 2).Direction = ParameterDirection.Output
command.ExecuteNonQuery()
XML_PaisOrigen = command.Parameters(1).Value.ToString
conexion.Close()
Catch ex As Exception
MsgBox(ex.Message & vbCrLf & "Error al ejecutar << " & ex.Message, MsgBoxStyle.Critical, "Test")
End Try
This how I call the SP in DB in Mysql and works perfect.
这就是我如何在 Mysql 中调用 DB 中的 SP 并且完美运行。
SET @Cod_Dua=1;
CALL TraerPaisOrigen(@Cod_Dua,@_PaisOrigen);
SELECT @_PaisOrigen;
I am really losing my mind, I have look tutorials and video tutorials and all they do the same or similar. What else could be that SP is not sending me an answer from DB? I have test this and doesn't bring nothing. Always goes to the else.
我真的疯了，我看过教程和视频教程，它们都做相同或相似的事情。SP 没有从 DB 向我发送答复还有什么可能？我对此进行了测试，并没有带来任何东西。总是去别的。
If cmd.ExecuteNonQuery() > 0 Then
XML_PaisOrigen = command.Parameters(1).Value.ToString
Else
MsgBox("Nothing!")
End If
