上传功能的页面代码（upload.aspx）：

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="upload.aspx.cs" Inherits="upload" %>

上传功能的服务端代码（upload.aspx.cs）

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.IO;

public partial class upload : System.Web.UI.Page
{
string picPath = "";
string picServer = "/upload";
protected string itemID = "";
protected void Page_Load(object sender, EventArgs e)
{

if (Request.QueryString["id"] != null)
{
itemID = Request.QueryString["id"];
}

if (IsPostBack)
{
picPath = Server.MapPath("\\upload");
doUpload();
}
}

protected void doUpload()
{
try
{
HttpPostedFile file = file1.PostedFile;
string strNewPath = GetSaveFilePath() + GetExtension(file.FileName);
file.SaveAs(picPath+strNewPath);
string urlPath = picServer + strNewPath;
urlPath = urlPath.Replace("\\", "/");
WriteJs("parent.uploadsuccess('" + urlPath + "','" + itemID + "'); ");

}
catch (Exception ex)
{
WriteJs("parent.uploaderror();");
}
}

private string GetExtension(string fileName)
{
try
{
int startPos = fileName.LastIndexOf(".");
string ext = fileName.Substring(startPos, fileName.Length - startPos);
return ext;
}
catch (Exception ex)
{
WriteJs("parent.uploaderror('" + itemID + "');");
return string.Empty;
}
}

private string GetSaveFilePath()
{
try
{
DateTime dateTime = DateTime.Now;
string yearStr = dateTime.Year.ToString(); ;
string monthStr = dateTime.Month.ToString();
string dayStr = dateTime.Day.ToString();
string hourStr = dateTime.Hour.ToString();
string minuteStr = dateTime.Minute.ToString();
string dir = dateTime.ToString(@"\\yyyyMMdd");
if (!Directory.Exists(picPath + dir))
{
Directory.CreateDirectory(picPath + dir);
}
return dir + dateTime.ToString("\\\\yyyyMMddhhmmssffff");
}
catch (Exception ex)
{
WriteJs("parent.uploaderror();");
return string.Empty;
}
}

protected void WriteJs(string jsContent)
{
this.Page.RegisterStartupScript("writejs","");
}

}

基本上就是这些，重点请看第一部份的代码，主要是JS控件显示，还有一个重点是upload.aspx调用父级页面的方法这些实现。

Javascript无刷新上传演示地址:http://www.wathon.com/opensource/js/ajaxuploadv1/upload.html
源代码下载地址：http://www.wathon.com/opensource/js/ajaxuploadv1/ajaxupload_src.zip
无刷新上传在编辑框中的应用演示:http://www.cnblogs.com/Files/huacn/ajaxupload_example.zip