Question

我很难解决此错误

将varchar值转换为Integer
时转换失败

代码似乎运行正常，我在其他代码上使用它，但唯一的区别是我使用的主键，对于这个我用了一个整数，而在其他代码我使用nvarchar为他们首要的关键。感谢您提前得到任何答案。

这是我的代码：

     Private Sub deleteIndv()

    Dim result
    Dim id As String = Me.DataGridView2.CurrentRow.Cells(0).Value

    Using cmd As New SqlClient.SqlCommand

        result = MsgBox(" Are You Sure You Want to Delete the Selected Row ? ", MsgBoxStyle.YesNo)

        TextBox2.Text = Me.DataGridView2.CurrentRow.Cells(0).Value.ToString

        '  Try

        If result = Windows.Forms.DialogResult.No Then

            Exit Sub

        Else

            If con.State = ConnectionState.Closed Then

                con.Open()

            End If

            cmd.Connection = con

            cmd.CommandText = "DELETE FROM IndvReports WHERE Id_indv = " & id

            cmd.Parameters.AddWithValue("@id", id)

            cmd.ExecuteNonQuery()

            Me.DataGridView2.Rows.Remove(Me.DataGridView2.CurrentRow)

            MsgBox(" Record Successfully Deleted! ", MsgBoxStyle.Information)

            cmd.Parameters.Clear()

        End If

        'Catch ex As Exception

        ' MsgBox(" Error Deleting Records! ", MsgBoxStyle.Exclamation)

        ' End Try

        cmd.Parameters.Clear()

    End Using

    If con.State = ConnectionState.Open Then

        con.Close()

    End If

Answer 1

错误由SQL生成。你确定下面的行实际返回并整数？：

Dim id As String = Me.DataGridView2.CurrentRow.Cells(0).Value

首先测试它（以下示例中的内容）：

 Dim g As String
 Try
      Dim l As Integer = Integer.Parse(g)
      'If successful then save action'

 Catch ex As Exception
      'Warn about error'

 End Try

Answer 2

我解决了我的问题。问题是这个“Dim id As String = Me.DataGridView2.CurrentRow.Cells（0）.Value”我刚刚在表上指定了Id_indv的确切单元格数我将其从（0）更改为（18）列所在的列我的PK被找到了。谢谢那些帮助我解决这个问题的人。以下是其他参考的工作代码：

    Dim result
    Dim id As String = Me.DataGridView2.CurrentRow.Cells(18).Value

    Using cmd As New SqlClient.SqlCommand

        result = MsgBox(" Are You Sure You Want to Delete the Selected Row ? ", MsgBoxStyle.YesNo)

        '  Try

        If result = Windows.Forms.DialogResult.No Then

            Exit Sub

        Else

            If con.State = ConnectionState.Closed Then

                con.Open()

            End If

            cmd.Connection = con

            cmd.CommandText = "DELETE FROM IndvReports WHERE Id_indv = " & id

            cmd.Parameters.AddWithValue("@id", id)

            cmd.ExecuteNonQuery()

            Me.DataGridView2.Rows.Remove(Me.DataGridView2.CurrentRow)

            MsgBox(" Record Successfully Deleted! ", MsgBoxStyle.Information)

            cmd.Parameters.Clear()

        End If

        'Catch ex As Exception

        ' MsgBox(" Error Deleting Records! ", MsgBoxStyle.Exclamation)

        ' End Try

        cmd.Parameters.Clear()

    End Using

    If con.State = ConnectionState.Open Then

        con.Close()

    End If

错误：将varchar值转换为Integer时转换失败

2 个答案: