ASP.NET FileUpload用法

文件类型验证  
protected void Button1_Click(object sender, EventArgs e)  

{  

    if (FileUpload1.HasFile)  

    {  

        fileExt = System.IO.Path.GetExtension(FileUpload1.FileName);  

        if (fileExt == ".jpg" || fileExt == ".gif")  

        {  

            try

            {  

                FileUpload1.SaveAs(Server.MapPath("upload") + "\\" + FileUpload1.FileName);  

                Label1.Text = "客户端路径：" + FileUpload1.PostedFile.FileName + "<br>" +  

                              "文件名：" + System.IO.Path.GetFileName(FileUpload1.FileName) + "<br>" +  

                              "文件扩展名：" + System.IO.Path.GetExtension(FileUpload1.FileName) + "<br>" +  

                              "文件大小：" + FileUpload1.PostedFile.ContentLength + " KB<br>" +   

                              "文件MIME类型：" + FileUpload1.PostedFile.ContentType + "<br>" +  

                              "保存路径：" + Server.MapPath("upload") + "\\" + FileUpload1.FileName;  

            }  

            catch (Exception ex)  

            {  

                Label1.Text = "发生错误：" + ex.Message.ToString();  

            }  

        }  

        else

        {  

            Label1.Text = "只允许上传jpg、gif文件！";  

        }  

    }  

    else

    {  

        Label1.Text = "没有选择要上传的文件！";  

    }  

}  

上传  
protected void Button1_Click(object sender, EventArgs e)  

{  

    if (FileUpload1.HasFile)  

    {  

        try

        {  

            FileUpload1.SaveAs(Server.MapPath("upload") + "\\" + FileUpload1.FileName);  

            Label1.Text = "客户端路径：" + FileUpload1.PostedFile.FileName + "<br>" +  

                          "文件名：" + System.IO.Path.GetFileName(FileUpload1.FileName) + "<br>" +  

                          "文件扩展名：" + System.IO.Path.GetExtension(FileUpload1.FileName) + "<br>" +  

                          "文件大小：" + FileUpload1.PostedFile.ContentLength + " KB<br>" +   

                          "文件MIME类型：" + FileUpload1.PostedFile.ContentType + "<br>" +  

                          "保存路径：" + Server.MapPath("upload") + "\\" + FileUpload1.FileName;  

        }  

        catch (Exception ex)  

        {  

            Label1.Text = "发生错误：" + ex.Message.ToString();  

        }  

    }  

    else

    {  

        Label1.Text = "没有选择要上传的文件！";  

    }  

}  


补充上传限制  
<system.web>  
    <httpRuntime maxRequestLength="40690" executionTimeout="6000" />  

</system.web>  

maxRequestLength表示可上传文件的最大值，executionTimeout表示ASP.NET关闭前允许发生的上载秒数。