Asp.net中FileUpload控件实现图片上传并带预览显示

1 <asp:FileUpload ID="FileUpload" runat="server" />
2 <asp:Button ID="BtnUp" runat="server" onclick="BtnUp_Click" Text="上 传" />
3 <asp:Label ID="LabMsg" runat="server"></asp:Label>
4 <img id="img" runat="server" src="" />

 1  /// <summary>
 2         /// 上传单一图片——有“选择”+“上传”两个按钮
 3         /// </summary>
 4         /// <param name="sender"></param>
 5         /// <param name="e"></param>
 6         protected void BtnUp_Click(object sender, EventArgs e)
 7         {
 8             if (FileUpload.HasFile)
 9             {
10                 string savePath = Server.MapPath("~/upload/");//指定上传文件在服务器上的保存路径
11                 //检查服务器上是否存在这个物理路径，如果不存在则创建
12                 if (!System.IO.Directory.Exists(savePath))
13                 {
14                     System.IO.Directory.CreateDirectory(savePath);
15                 }
16                 savePath = savePath + "\\" + FileUpload.FileName;
17                 FileUpload.SaveAs(savePath);
18                 LabMsg.Text = string.Format("<a href=‘upload/{0}‘>upload/{0}</a>", FileUpload.FileName);
19                 this.img.Src = "upload/" + FileUpload.FileName;
20             }
21             else
22             {
23                 LabMsg.Text = "你还没有选择上传文件!";
24             }
25         }