<script language="javascript">function $(o){return document.getElementById(o);}function CheckImgCss(o,img){ if (!//.((jpg)|(bmp)|(gif)|(png))$/ig.test(o.value)) { alert('只能上传jpg,bmp,gif,png格式图片!'); o.outerHTML = o.outerHTML; } else { $(img).filters.item("DXImageTransform.Microsoft.AlphaImageLoader").src=o.value; //$('Image1').src = o.value;//这里IE7已经不支持了。所以才有上面的方法。 }}</script> <form id="form1" runat="server"> <div><h1>一次上传多个图片并预览,请选择图片:</h1> <asp:FileUpload ID="FileUpload1" onchange="CheckImgCss(this, 'img');" runat="server" /> <asp:FileUpload ID="FileUpload2" onchange="CheckImgCss(this, 'img');" runat="server" /> <asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="上传" /> <div id="img" style="filter:progid:DXImageTransform.Microsoft.AlphaImageLoader(src=<%= pic%>,sizingMethod=scale);width:102px;height:100px;"></div> </div> 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;namespace UploadPicture{ public partial class _Default : System.Web.UI.Page { //该变量用来修改的的时候的默认值。例如上传自己的头像,如果用户修改头像,这里可以显示他原来的头像。 public string pic = "http://www.svnhost.cn/images/logo.gif"; protected void Page_Load(object sender, EventArgs e) { } protected void Button1_Click(object sender, EventArgs e) { Random r = new Random(); //这样循环,可以同时上传多个文件。前台已经有文件格式的判断,有错误提示了。这里只要过滤掉非法文件即可,无需提示了。 for (int i = 0; i < Request.Files.Count; i++) { if (Request.Files[i].ContentLength > 0) { string ex = System.IO.Path.GetExtension(Request.Files[i].FileName).ToLower(); if (".jpg.gif.png.bmp".Contains(ex)) { string newFileName = DateTime.Now.ToString("yyyyMMddHHmmss") + r.Next(100, 999).ToString() + ex; //保存文件名到数据库 //xxxxxxxxxxxxxxxx //xxxxxxxxxxxxxxxx Request.Files[i].SaveAs(Server.MapPath(newFileName)); pic = newFileName; } } } } }}