FileUpload控件

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 FileUpload : System.Web.UI.Page
...{
    protected void Page_Load(object sender, EventArgs e)
    ...{

    }
    protected void Button1_Click(object sender, EventArgs e)
    ...{
        bool fileOK = false;
        string path = Server.MapPath("~/temp/");
        if (FileUpload1.HasFile)
        ...{
            String fileExtension = System.IO.Path.GetExtension(FileUpload1.FileName).ToLower();
            String[] allowedExtension =...{ ".gif", ".png", ".bmp", ".jpg" };
            for (int i = 0; i < allowedExtension.Length; i++)
            ...{
                if (fileExtension == allowedExtension[i])
                ...{ fileOK = true; }
            }
        }
        if (fileOK)
        ...{
            try
            ...{
                FileUpload1.SaveAs(path + FileUpload1.FileName);
                Label1.Text = "文件上传成功！";
            }
            catch (Exception ex)
            ...{ Label1.Text = "文件上传不成功！"; }
        }
        else
        ...{ Label1.Text = "只能上传图片文件！"; }
    }
}