我需要在用户单击按钮时处理(服务器端)大量数据(文件)。我想显示正在处理的每个文件名的运行摘要。我一直在尝试使用 UpdatePanel 控件来完成此操作，但只发生最后一次更新。下面是我创建的一些简单代码来模拟该问题(它应该从 1 计数到 10，但会等待 5 秒并输出 10):
<%@ Page Language="C#" %>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
<script runat="server">
protected void Page_Load(object sender, EventArgs e)
{
ScriptManager1.RegisterAsyncPostBackControl(Button1);
}
protected void Button1_Click(object sender, EventArgs e)
{
for (int i = 1; i <= 10; i++)
{
Label1.Text = i.ToString();
System.Threading.Thread.Sleep(500);
UpdatePanel1.Update();
}
}
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="Button" />
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:Label ID="Label1" runat="server" Text="Label"></asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
</div>
</form>
</body>
</html>
有办法让这个工作成功吗？或者也许有更好的方法？
提前致谢， 杰森
最佳答案
您需要使用 ajax 调用服务器。我从我之前的一个项目中复制了这段代码，它的代码有点长。尝试一下，让我知道它是否有效。
page1.aspx
<asp:Content ID="Content1" ContentPlaceHolderID="head" Runat="Server">
<script type="text/javascript">
function BeginProcess() {
// Create an iframe.
var iframe = document.createElement("iframe");
// Point the iframe to the location of
// the long running process.
iframe.src = "Process.aspx";
// Make the iframe invisible.
iframe.style.display = "none";
// Add the iframe to the DOM. The process
// will begin execution at this point.
document.body.appendChild(iframe);
// Disable the button and blur it.
document.getElementById('trigger').blur();
}
function UpdateProgress(PercentComplete, Message) {
document.getElementById('ContentPlaceHolder2_lbDownload').setAttribute("disabled", "true");
document.getElementById('trigger').value = PercentComplete + '%: ' + Message;
}
</script>
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder2" Runat="Server">
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<input type="submit" value="Start BackUp Process!"
id="trigger" onclick="BeginProcess(); return false;"
style="width: 250px;" />
</ContentTemplate>
</asp:UpdatePanel>
<asp:UpdateProgress ID="UpdateProgress1"
AssociatedUpdatePanelID="UpdatePanel1" runat="server">
<ProgressTemplate>
</ProgressTemplate>
</asp:UpdateProgress>
</asp:Content>
Process.aspx.cs
public partial class Process : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
StringBuilder SB = new StringBuilder();
// Padding to circumvent IE's buffer.
Response.Write(new string('*', 256));
Response.Flush();
// Initialization
UpdateProgress(0, "Initializing task.");
try
{
foreach (yourloophere)
{
UpdateProgress(increment, db.Name + " Backup Started....");
//your process code
UpdateProgress(increment, db.Name + " Backup Completed!");
//your process code
SB.Append(db.Name + "BackUp Complted!");
//your process code
SB.Append("<br/>");
}
// All finished!
UpdateProgress(100, "All Database BackUp Completed!");
}
catch (Exception ex)
{
UpdateProgress(0, "Exception: " + ex.Message);
SB.Append("Back Up Failed!");
SB.Append("<br/>");
SB.Append("Failed DataBase: " + DBName);
SB.Append("<br/>");
SB.Append("Exception: " + ex.Message);
}
}
protected void UpdateProgress(double PercentComplete, string Message)
{
// Write out the parent script callback.
Response.Write(String.Format("<script type=\"text/javascript\">parent.UpdateProgress({0}, '{1}');</script>", PercentComplete, Message));
// To be sure the response isn't buffered on the server.
Response.Flush();
}
}
关于asp.net - 如何在服务器上处理某些内容时更新状态标签？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/15774629/