从客户端上传文件到服务器端,
一般来讲,做应用系统, 总是会遇到从客户端通过Web页面上传文件到服务器端的需求.
这种需求一般都会想做批量上传.
但是HTML中的input上传, 一个input控件只能选择一个文件, 同时上传多文件, 如果做到简单易用就需要花点时间了.
网上基本的做法都是google的那种上载文件的 模式, 就是先一个一个选择, 然后批量上传, 这种模式虽然不是非常方便, 但是也还好使.
demo代码就不用自己写了, 上网上荡了一个, 希望原创作者不要见怪.
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="Demo._Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script language="JavaScript">
function addFile()
{
var str = '<INPUT type="file" size="50" NAME="File">'
document.getElementById('MyFile').insertAdjacentHTML("beforeEnd",str)
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server" enctype="multipart/form-data">
<input type="button" value="增加(Add)" onclick="addFile()">
<input onclick="this.form.reset()" type="button" value="重置(ReSet)">
<asp:Button Runat="server" Text="上传" ID="Upload" OnClick="Upload_Click1" ></asp:Button>
<div id="MyFile">
<input type="file" name="File" />
</div>
</form>
</body>
</html>
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 Demo
{
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void Upload_Click1(object sender, EventArgs e)
{
HttpFileCollection _files = System.Web.HttpContext.Current.Request.Files;
for (int i = 0; i < _files.Count; i++)
{
_files[i].SaveAs(Server.MapPath("~/Files/" + _files[i].FileName));
}
}
}
}
这段代码中尤其需要注意 enctype="multipart/form-data",这在上传文件的时候尤其需要注意, W3C对这个的解释如下:
enctype = content-type [CI]
This attribute specifies the content type used to submit the form to the server (when the value of method is "post"). The default value for this attribute is "application/x-www-form-urlencoded". The value "multipart/form-data" should be used in combination with the INPUT element,type="file".