Question

如何调试以下代码？

Dim deleteok As String = MsgBox("Do you really want to delete this record", MsgBoxStyle.YesNo, "updating records")
        If vbYes Then
            Try
                con.Open()
                cmd.Connection = con
                cmd.CommandText = "Delete From TB_stinfo where id=?"
                cmd.Parameters.Add(New OleDbParameter("?", TextBox1.Text))
                cmd.ExecuteNonQuery()
                MessageBox.Show("one record is deleted")
            Catch ex As Exception
                MessageBox.Show("Error while deleting record on table..." & ex.Message, "Delete Records")
            Finally
                dt.Clear()
                Form1_Load(sender, e)
                clear()
                checkcon()
            End Try
        Else
            MsgBox("This record is not deleted")
        End If

Answer 1

我重新格式化了代码，因此它更具可读性：

Dim deleteok As String = MsgBox("Do you really want to delete this record", MsgBoxStyle.YesNo, "updating records") 
If vbYes Then 
    Try 
        con.Open() 
        cmd.Connection = con cmd.CommandText = "Delete From TB_stinfo where id=?" 
        cmd.Parameters.Add(New OleDbParameter("?", TextBox1.Text)) 
        cmd.ExecuteNonQuery() 
        MessageBox.Show("one record is deleted") 
    Catch ex As Exception 
        MessageBox.Show("Error while deleting record on table..." & ex.Message, "Delete Records") 
    Finally 
        dt.Clear() 
        Form1_Load(sender, e) 
        clear() 
        checkcon() 
    End Try 
Else 
    MsgBox("This record is not deleted") 
End If

我在这里看到的头号问题是，我们看不到您要删除的密钥值是什么，也不知道要删除的表中数据的格式。无法确定此代码究竟出现了什么问题。

我的建议是在这一行cmd.ExecuteNonQuery()上设置一个断点，看看TextBox1.Text的值是什么，并确保它符合您的预期，查找前导/尾随空格或其他任何＆＃39;意想不到的......除此之外，在上下文方面还没有其他的东西可以继续。

删除按钮代码有时工作

1 个答案: