Question

正在努力从VB.net访问SQL Server存储过程：

DECLARE @R INT
DECLARE @trm VARCHAR(255)
SET @trm = 'PartNumber'

EXECUTE @R = [dbo].[usp_CannedGlobalSearch] @trm

此SQL语句在SQL Server Management Studio中返回12列。效果很好。

Dim StoredConn As OdbcConnection = New OdbcConnection(SQLRdrConnectString)
Dim StoredCommand As New OdbcCommand
("CALL usp_CannedGlobalSearch (?)", StoredConn)
StoredCommand.CommandType = CommandType.StoredProcedure
StoredCommand.CommandText = "{? = CALL usp_CannedGlobalSearch(?)}"
StoredCommand.Parameters.Add("@RC", OdbcType.Int)  'this is the result
StoredCommand.Parameters.Add("@trm", OdbcType.VarChar)   'sending a search string
StoredCommand.Parameters("@term").Value = "PartNumber"
StoredConn.Open()
Dim TestInt As Integer = StoredCommand.ExecuteNonQuery()

运行时结果：

错误[HY105] [Microsoft] [ODBC SQL Server驱动程序]无效的参数类型。

Answer 1

以下是使用显示的参数从VB.NET调用SQL Server中的存储过程的方法：

Dim testInt As Integer = -1

Using conn As New SqlConnection(SQLRdrConnectString)
    Using cmd As New SqlCommand("usp_CannedGlobalSearch", conn)
        cmd.CommandType = CommandType.StoredProcedure
        cmd.Parameters.Add(New SqlParameter With {
                           .ParameterName = "@trm",
                           .SqlDbType = SqlDbType.VarChar,
                           .Size = 255,
                           .Value = "PartNumber"})

        conn.Open()
        Dim res As Object = cmd.ExecuteScalar()
        If res IsNot Nothing Then
            testInt = Convert.ToInt32(res)
        End If

    End Using
End Using

带有Dim res As Object...的部分将完全不考虑返回任何内容，甚至不返回NULL，并且testInt的值将为-1，因此您可以进行检查。如果存储过程始终返回一个整数，则可以仅用一行替换它：

testInt = Convert.ToInt32(cmd.ExecuteScalar())

使用SQL Server存储过程在VB.NET失败

1 个答案: