Question

我想知道如何检查我的程序是否已连接到数据库。

这是我的代码::

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    conn.Open()
    If conn.State = ConnectionState.Open Then
        MsgBox("YOU ARE CONNECTED TO THE DATABASE")
    Else
        MsgBox("YOU ARE NOT CONNECTED TO THE DATABASE, CONTACT YOUR ADMINISTRATOR")
    End If
    conn.Close()
End Sub

如果连接字符串正确，则此代码正常工作，消息显示为open;但是当连接错误时，错误结果是：

Login failed for user

以下是我想要发生的算法：

If thisProgram is connected then
 Messagebox ("YOU ARE CONNECTED TO THE DATABASE")
Else
 MessageBox ("YOU ARE NOT CONNECTED TO THE DATABASE, CONTACT YOUR ADMINISTRATOR")
End If

请帮助谢谢

Answer 1

很简单，你可以把尝试和捕获。

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    Try
       conn.Open()
       If conn.State = ConnectionState.Open Then
           MsgBox("open")
       Else
           MsgBox("no")
       End If
       conn.Close()
    Catch
       MsgBox("no")
    End Try
End Sub

如何检查是否连接到数据库

1 个答案: