Question

我是ASP.NET的新手，所以可能我的问题很容易......但是我浪费了很多时间而没有成功。
我的部分内容是

<asp:UpdatePanel ID="pnlFileUpload" runat="server">
    <ContentTemplate>
        <ajaxToolkit:AsyncFileUpload ID="upload" runat="server" OnUploadedComplete="upload_UploadedComplete"
            OnUploadedFileError="upload_UploadedFileError" UploaderStyle="Modern" UploadingBackColor="Yellow"
            Width="400px" />
    </ContentTemplate>
</asp:UpdatePanel>
<asp:UpdatePanel ID="pnlFileError" runat="server" UpdateMode="Conditional">
    <ContentTemplate>
        <asp:Label ID="lblFileError" runat="server" Text="errFile" Visible="false"></asp:Label>
    </ContentTemplate>
    <Triggers>
        <asp:AsyncPostBackTrigger ControlID="upload" EventName="UploadedComplete" />
    </Triggers>
</asp:UpdatePanel>

当用户上传（以ajaxToolkit:AsyncFileUpload开头）结束时，会调用upload_UploadedComplete 示例代码为：

protected void upload_UploadedComplete(object sender, AjaxControlToolkit.AsyncFileUploadEventArgs e)
{
    int size = upload.PostedFile.ContentLength;
    if (size > maxsize)
    {
        lblFileError.Text = 'File too big...';
        lblFileError.ForeColor = System.Drawing.Color.Red;
        lblFileError.Visible = true;
        pnlFileError.Update();
    }
}

但lblFileError从未显示过......为什么？！？

Answer 1

AsyncFileupload不需要updatePanel（不需要AJAx工具包控件）。因为他们把它作为内置的。删除fileupload UpdatePanel并再次测试

似乎你不能以这种方式做到这一点。基于AjaxControlToolkitSampleSite向用户显示有关上传文件的消息，您应该使用“ScriptManager.RegisterClientScriptBlock”，如下所示：

protected void upload_UploadedComplete(object sender,  AjaxControlToolkit.AsyncFileUploadEventArgs e)
{
   int size = upload.PostedFile.ContentLength;
   if (size > maxsize)
    {
      ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "error", "top.$get(\"" + lblFileError.ClientID + "\").innerHTML = 'File too big...';", true);

    }
}

UpdatePanel没有刷新

1 个答案: