ImageButton问题- CommandArgument不工作

Question

我在asp.net是个新手。

我正在尝试使用ImageButton链接到另一个页面。ImageButton在转发器中，代码如下：

<ul id = "ulMap"> 
    <asp:Repeater ID="Repeater1" runat="server" >
        <ItemTemplate>
            <li>
                <asp:ImageButton ID="ImageButton1" 
                                 CommandArgument='<%#Eval("Nav_ID") %>' 
                                 runat="server" 
                                 ImageUrl="~/Icons/Ny_mappa.png"
                                 onclick="ImageButton1_Click" />
                <br />
                <asp:LinkButton ID="lnkButton" 
                                CommandArgument='<%#Eval("Nav_ID") %>' 
                                runat="server" 
                                onclick="LinkButton3_Click" 
                                Text='<%#Eval("Nav_Name") %>'></asp:LinkButton>
            </li>
        </ItemTemplate>
    </asp:Repeater> 
</ul>

后面的代码如下：

protected void LinkButton3_Click(object sender, EventArgs e)
{
    Guid guid = new Guid(((LinkButton)sender).CommandArgument);

    var query = from n in dc.Nemanet_Navigations
                where n.UserId == userGuid && n.Nav_pID == guid
                orderby n.Nav_Name ascending
                select n;

    Repeater1.DataSource = query;
    Repeater1.DataBind();
}

protected void ImageButton1_Click(object sender, ImageClickEventArgs e)
{
    Guid guid = new Guid(((ImageButton)sender).CommandArgument);

    var query = from n in dc.Nemanet_Navigations
                where n.UserId == userGuid && n.Nav_pID == guid
                orderby n.Nav_Name ascending
                select n;

    Repeater1.DataSource = query;
    Repeater1.DataBind();
}

嗯，对于LinkButton来说，这很好用，但对于ImageButton就不行了。Protected void ImageButton1_Click永远不会发生。有人能帮上忙吗？

Answer 1

我认为您需要处理Repeater_ItemCommand事件才能使其正常工作。它可能还会节省一些代码。

MSDN Repeater ItemCommand

此外，如果您链接到另一个页面，您是否需要回发到该页面，然后执行某种重定向，或者在新页面中具有该逻辑是否更有意义？

Answer 2

你应该使用OnCommand，而不是OnClick。就像这样。

<ul id = "ulMap"> 
    <asp:Repeater ID="Repeater1" runat="server" >
        <ItemTemplate>
            <li>
                <asp:ImageButton ID="ImageButton1" 
                                 CommandArgument='<%#Eval("Nav_ID") %>' 
                                 runat="server" 
                                 ImageUrl="~/Icons/Ny_mappa.png"
                                 OnCommand="ImageButton1_Click" />
                <br />
                <asp:LinkButton ID="lnkButton" 
                                CommandArgument='<%#Eval("Nav_ID") %>' 
                                runat="server" 
                                OnCommand="LinkButton3_Click" 
                                Text='<%#Eval("Nav_Name") %>'></asp:LinkButton>
            </li>
        </ItemTemplate>
    </asp:Repeater> 
</ul>

还有这个(注意CommandEventArgs而不是EventArgs和ImageClickEventArgs)：

protected void LinkButton3_Click(object sender, CommandEventArgs e)
{
    Guid guid = new Guid(e.CommandArgument);

    var query = from n in dc.Nemanet_Navigations
                where n.UserId == userGuid && n.Nav_pID == guid
                orderby n.Nav_Name ascending
                select n;

    Repeater1.DataSource = query;
    Repeater1.DataBind();
}

protected void ImageButton1_Click(object sender, CommandEventArgs e)
{
    Guid guid = new Guid(e.CommandArgument);

    var query = from n in dc.Nemanet_Navigations
                where n.UserId == userGuid && n.Nav_pID == guid
                orderby n.Nav_Name ascending
                select n;

    Repeater1.DataSource = query;
    Repeater1.DataBind();
}

Answer 3

您不能像这样处理转发器子控件的服务器端事件。

这样想吧--如果有100个按钮，那么每个按钮需要100个事件处理程序。ImageButton1_Click仅适用于id为1的ImageButton。

答案是为您的中继器连接ItemCommand事件。

如下所示：

<asp:repeater id = "Repeater`" runat = "server" onItemCommand = "SomeEvent">

然后处理触发此事件的所有按钮的"SomeEvent“：

protected void SomeEvent ( Object src, RepeaterCommandEventArgs e ) {  
      var whoClickedMe = ((ImageButton) e.CommandSource );
}

Here's上有一篇关于这方面的好文章。