Question

你好我试图在一个表单上处理多个数据库连接，我有一些代码，但运气不好。所以我的问题是实现try catch的最佳方法是什么，我将在何处调用该方法来处理连接，并举例说明我的代码。

<script runat="server">    
    Protected Sub SqlDataSource12_Selecting(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.SqlDataSourceSelectingEventArgs)
    End Sub

    Protected Sub loadMe(ByVal sender As Object, ByVal e As System.EventArgs)    
        Try
            Dim conn As New Data.SqlClient.SqlConnection(ConfigurationManager.ConnectionStrings("BODataConnectionString54").ConnectionString)
            conn.Open()
            conn.Close()
            ListView3.DataSourceID = "SqlDataSource12"
        Catch ex As System.Data.SqlClient.SqlException
            error10.Visible = True
        End Try  
      End Sub

    Protected Sub ListView3_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs)

    End Sub 
</script>

我实现了loadMe到身体。

<asp:Content ID="Content2" ContentPlaceHolderID="topContent" Runat="Server" >
    <body id="Body1" runat="server" onload="loadMe">

ListView3_SelectedIndexChanged到ListView。

<asp:ListView ID="ListView3" runat="server" ItemPlaceholderID="itemPlaceHolder1" DataSourceID="SqlDataSource12" OnSelectedIndexChanged="ListView3_SelectedIndexChanged">

SqlDataSource12_Selecting to SqlDataSource。

<asp:SqlDataSource ID="SqlDataSource12" runat="server" ConnectionString="
<%$ ConnectionStrings:BODataConnectionString54 %>" 
                   SelectCommand="SELECT..... "
                   onselecting="SqlDataSource12_Selecting"
                   ProviderName="<%$ ConnectionStrings:BODataConnectionString54.ProviderName %>">
                        <SelectParameters>

最后我希望捕获的消息显示何时没有与数据库的连接。

<asp:Label runat="server" ID="error10" Text="Store could not be loaded" Visible="False" />

任何帮助都会非常感谢你。

Answer 1

所以我发现我只需要一次尝试捕获“loadMe”，并在catch中添加“ListView3.Visible = False”并将“Visible =”True“”添加到“ListView3”。这是一个例子

<script runat="server">


    Protected Sub loadMe(ByVal sender As Object, ByVal e As System.EventArgs)


        Try
            Dim conn As New Data.SqlClient.SqlConnection(ConfigurationManager.ConnectionStrings("BODataConnectionString54").ConnectionString)
            conn.Open()
            conn.Close()
            ListView3.DataSourceID = "SqlDataSource12"
        Catch ex As System.Data.SqlClient.SqlException           
            ListView3.Visible = False
            error10.Visible = True
        End Try


    End Sub


</script>
..
...
....
   <body id="Body1" runat="server" onload="loadMe">
..
...
....
   <asp:ListView ID="ListView3" runat="server" Visible="True" ItemPlaceholderID="itemPlaceHolder1" DataSourceID="SqlDataSource12" >

使用VB ASP处理SQL Server连接

1 个答案: