关于在设计SqlDataAdapter并使用带有参数的 SQL或存储过程时，出现的必须声明 @参数名 的错误解决方案

 

关于在设计SqlDataAdapter并使用带有参数的 SQL或存储过程时，出现的必须声明 @参数名 的错误解决方案

 

错误码代码如下：

Dim dbcon As New SqlConnection("Data Source=localhost;database=Northwind;Integrated Security=True")

        Dim cmd As New SqlCommand("select * from Orders where OrderID=@ID", dbcon)

        Dim para As New SqlParameter

        With para

            .ParameterName = "@ID"

            .Direction = ParameterDirection.Input

            .SqlDbType = SqlDbType.Int

            .Value = TextBox1.Text

        End With

        cmd.Parameters.Add(para)

Dim adapter As New SqlDataAdapter(cmd.CommandText, dbcon)   '错误

        Dim dataset As New DataSet

        adapter.Fill(dataset)

        DataGridView1.DataSource = dataset.Tables(0)

 

错误提示如下：

正确代码如下：

        Dim dbcon As New SqlConnection("Data Source=localhost;database=Northwind;Integrated Security=True")

        Dim cmd As New SqlCommand("select * from Orders where OrderID=@ID", dbcon)

        Dim para As New SqlParameter

        With para

            .ParameterName = "@ID"

            .Direction = ParameterDirection.Input

            .SqlDbType = SqlDbType.Int

            .Value = TextBox1.Text

        End With

        cmd.Parameters.Add(para)

        Dim adapter As New SqlDataAdapter(cmd)

        Dim dataset As New DataSet

        adapter.Fill(dataset)

        DataGridView1.DataSource = dataset.Tables(0)

 

这其中只修改了一个地方，就是实例化 SqlDataAdapter对象的时候，Dim adapter As New SqlDataAdapter(cmd)，而不是 Dim adapter As New SqlDataAdapter(cmd.CommandText, dbcon)

 

请注意：如下代码并没有错：

        Dim dbcon As New SqlConnection("Data Source=localhost;database=Northwind;Integrated Security=True")

        Dim cmd As New SqlCommand("select * from Orders where OrderID=@ID", dbcon)

        Dim para As New SqlParameter

        With para

            .ParameterName = "@ID"

            .Direction = ParameterDirection.Input

            .SqlDbType = SqlDbType.Int

            .Value = TextBox1.Text

        End With

        cmd.Parameters.Add(para)

        dbcon.Open()

        cmd.ExecuteNonQuery()