asp.net中fileupload上传文件的方法

//前台就随便拖一个FileUpload控件和一个button控件
 
<asp:FileUpload ID="FileUpload1" runat="server" /><br />
<asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="Button" />

//后台
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;

public partial class Manage_News_upload : System.Web.UI.Page
...{
    protected void Page_Load(object sender, EventArgs e)
    ...{

    }
    protected void Button1_Click(object sender, EventArgs e)
    ...{
        if (FileUpload1.HasFile)
        ...{
            string fileExrensio = System.IO.Path.GetExtension(FileUpload1.FileName).ToLower();//ToLower转化为小写
            string FileType = FileUpload1.PostedFile.ContentType;
            string UploadURL = Server.MapPath("~/upload/");//上传的目录
            if (FileType == "image/bmp" || FileType == "image/gif" || FileType == "image/jpeg" || FileType == "image/jpg" || FileType == "image/png")//判断文件类型
            ...{

                try
                ...{
                    if (!System.IO.Directory.Exists(UploadURL))//判断文件夹是否已经存在
                    ...{
                        System.IO.Directory.CreateDirectory(UploadURL);//创建文件夹
                    }

                    FileUpload1.PostedFile.SaveAs(UploadURL + FileUpload1.FileName);
                }
                catch 
                ...{
                    Response .Write ("失败");
                }
            }
            else
            ...{
                Response.Write("格式错误");
            }
        }
        else 
             Response.Write("请选择文件");
    }
}
		

  protected void Button1_Click(object sender, EventArgs e)
 ...{
     string filepath = Server.MapPath("upload") + "\\\\";
     HttpFileCollection uploadFiles = Request.Files;
     for (int i = 0; i 〈 uploadFiles.Count; i++)
     ...{
         HttpPostedFile postedFile = uploadFiles[i];
         try
         ...{
             if (postedFile.ContentLength > 0)
             ...{
                 Label1.Text += "文件 #" + (i + 1) + "：" + System.IO.Path.GetFileName(postedFile.FileName) + "〈br/>";
                 postedFile.SaveAs(filepath + System.IO.Path.GetFileName(postedFile.FileName));
             }
         }
         catch (Exception Ex)
         ...{
             Label1.Text += "发生错误： " + Ex.Message;
         }
     }
 }