在以前的Web应用中，上传文件是个很麻烦的事，现在有了.NET，文件上传变得轻而易举。下面的这个例子实现了多文件上传功能。可以动态添加输入表单，上传的文件数量没有限制。代码如下：
MultiUpload.aspx
<%@ Page Language="vb" AutoEventWireup="false" Codebehind="MultiUpload.aspx.vb"
Inherits="aspxWeb.MultiUpload" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >
<HTML>
<HEAD>
<title>多文件上传</title>
<script language="JavaScript">
function addFile()
{
var str = '<INPUT type="file" size="50" NAME="File">'
document.getElementById('MyFile').insertAdjacentHTML("beforeEnd",str)
}
</script>
</HEAD>
<body>
<form id="form1" method="post" runat="server" enctype="multipart/form-data">
<center>
<asp:Label Runat="server" ID="MyTitle"></asp:Label>
<P id="MyFile"><INPUT type="file" size="50" NAME="File"></P>
<P>
<input type="button" value="增加(Add)" onclick="addFile()">
<asp:Button Runat="server" Text="上传" ID="Upload"></asp:Button>
<input onclick="this.form.reset()" type="button" value="重置(ReSet)">
</P>
</center>
<P align="center">
<asp:Label id="strStatus" runat="server" Font-Names="宋体" Font-Bold="True"
Font-Size="9pt" Width="500px" BorderStyle="None" BorderColor="White"></asp:Label>
</P>
</form>
</body>
</HTML>
后代码：MultiUpload.aspx.vb
Public Class MultiUpload
Inherits System.Web.UI.Page
Protected WithEvents Upload As System.Web.UI.WebControls.Button
Protected WithEvents MyTitle As System.Web.UI.WebControls.Label
Protected WithEvents strStatus As System.Web.UI.WebControls.Label
#Region " Web Form Designer Generated Code "
'This call is required by the Web Form Designer.
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
End Sub
Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
'CODEGEN: This method call is required by the Web Form Designer
'Do not modify it using the code editor.
InitializeComponent()
End Sub
#End Region
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
MyTitle.Text = "<h3>多文件上传</h3>"
Upload.Text = "开始上传"
If (Me.IsPostBack) Then Me.SaveImages()
End Sub
Private Function SaveImages() As System.Boolean
'遍历File表单元素
Dim files As System.Web.HttpFileCollection = System.Web.HttpContext.Current.Request.Files
'状态信息
Dim strMsg As New System.Text.StringBuilder("上传的文件分别是：<hr color=red>")
Dim iFile As System.Int32
Try
For iFile = 0 To files.Count - 1
'检查文件扩展名字
Dim postedFile As System.Web.HttpPostedFile = files(iFile)
Dim fileName, fileExtension As System.String
fileName = System.IO.Path.GetFileName(postedFile.FileName)
If Not (fileName = String.Empty) Then
fileExtension = System.IO.Path.GetExtension(fileName)
strMsg.Append("上传的文件类型：" + postedFile.ContentType.ToString() + "<br>")
strMsg.Append("客户端文件地址：" + postedFile.FileName + "<br>")
strMsg.Append("上传文件的文件名：" + fileName + "<br>")
strMsg.Append("上传文件的扩展名：" + fileExtension + "<br><hr>")
'可根据扩展名字的不同保存到不同的文件夹
postedFile.SaveAs(System.Web.HttpContext.Current.Request.MapPath("images/") + fileName)
End If
Next
strStatus.Text = strMsg.ToString()
Return True
Catch Ex As System.Exception
strStatus.Text = Ex.Message
Return False
End Try
End Function
End Class
C# 版本
UpLoad.aspx
<%@ Page language="c#" Codebehind="UpLoad.aspx.cs" AutoEventWireup="false" Inherits="WebPortal.Upload" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >
<HTML>
<HEAD>
<title>多文件上传</title>
<script language="JavaScript">
function addFile()
{
var str = '<INPUT type="file" size="50" NAME="File">'
document.getElementById('MyFile').insertAdjacentHTML("beforeEnd",str)
}
</script>
</HEAD>
<body>
<form id="form1" method="post" runat="server" enctype="multipart/form-data">
<div align="center">
<h3>多文件上传</h3>
<P id="MyFile"><INPUT type="file" size="50" NAME="File"></P>
<P>
<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="开始上传" ID="UploadButton"></asp:Button>
</P>
<P>
<asp:Label id="strStatus" runat="server" Font-Names="宋体" Font-Bold="True" Font-Size="9pt"
Width="500px" BorderStyle="None" BorderColor="White"></asp:Label>
</P>
</div>
</form>
</body>
</HTML>
UpLoad.aspx.cs
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
namespace WebPortal
{
/// <summary>
/// UpLoad 的摘要说明。
/// 实现多文件上传
/// </summary>
public class Upload : System.Web.UI.Page
{
protected System.Web.UI.WebControls.Button UploadButton;
protected System.Web.UI.WebControls.Label strStatus;
private void Page_Load(object sender, System.EventArgs e)
{
/// 在此处放置用户代码以初始化页面
if (this.IsPostBack) this.SaveImages();
}
private Boolean SaveImages()
{
///'遍历File表单元素
HttpFileCollection files = HttpContext.Current.Request.Files;
/// '状态信息
System.Text.StringBuilder strMsg = new System.Text.StringBuilder();
strMsg.Append("上传的文件分别是：<hr color=red>");
try
{
for(int iFile = 0; iFile < files.Count; iFile++)
{
///'检查文件扩展名字
HttpPostedFile postedFile = files[iFile];
string fileName, fileExtension;
fileName = System.IO.Path.GetFileName(postedFile.FileName);
if (fileName != "")
{
fileExtension = System.IO.Path.GetExtension(fileName);
strMsg.Append("上传的文件类型：" + postedFile.ContentType.ToString() + "<br>");
strMsg.Append("客户端文件地址：" + postedFile.FileName + "<br>");
strMsg.Append("上传文件的文件名：" + fileName + "<br>");
strMsg.Append("上传文件的扩展名：" + fileExtension + "<br><hr>");
///'可根据扩展名字的不同保存到不同的文件夹
///注意：可能要修改你的文件夹的匿名写入权限。
postedFile.SaveAs(System.Web.HttpContext.Current.Request.MapPath("images/") + fileName);
}
}
strStatus.Text = strMsg.ToString();
return true;
}
catch(System.Exception Ex)
{
strStatus.Text = Ex.Message;
return false;
}
}
#region Web 窗体设计器生成的代码
override protected void OnInit(EventArgs e)
{
//
// CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的。
//
InitializeComponent();
base.OnInit(e);
}
/// <summary>
/// 设计器支持所需的方法 - 不要使用代码编辑器修改
/// 此方法的内容。
/// </summary>
private void InitializeComponent()
{
this.ID = "Upload";
this.Load += new System.EventHandler(this.Page_Load);
}
#endregion
}
}