Question

我使用以下语句作为参数。

.Parameters("@SearchValue").Value = TextBoxParentID.Text

此查询：

 objSqlCommand.CommandText = "Select ID " & _
                               "From Parents " & _
                              "Where ID = @SearchValue"

ID是SQL服务器数字列但我收到此错误：

error converting nvarchar to numeric

你能告诉我需要修改的代码吗？

Answer 1

此时您正在尝试分配字符串类型的值，并且参数绑定为字符串（nvarchar）。你需要先转换它。

    ' Let's suppose that this is a value from your textbox
    Dim strNumber As String = "12"

    ' Prepare a placeholder to convert your string value into integer
    Dim myInteger As Integer

    ' Try to convert
    If Int32.TryParse(strNumber, myInteger) Then
        'If the conversion is successful

        Dim myConnection As New SqlConnection("Your ConnectionString")
        Dim myCommand As New SqlCommand("INSERT INTO Foo(Bar) VALUES (@Bar", myConnection)

        'Use this syntax to assign values to parameters
        myCommand.Parameters.AddWithValue("Bar", myInteger)
    End If

此代码段也使用AddWithValue方法。我建议你使用这种方法。

将nvarchar转换为数字时出错

1 个答案: