怎么同时上传多张图片并预览图片信息
后台代码：
using System;
using System.Data;
using System.Configuration;
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;
using System.Collections;
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
/// <summary>
/// 增加按钮
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
protected void btnAdd_Click(object sender, EventArgs e)
{
ArrayList arraylist = new ArrayList();
if (Session["UPLOAD"] == null)
{
//检查是否有文件要上传
if (this.FileUpload1.HasFile)
{
if (this.FileUpload1.PostedFile.ContentLength > 4096000)
{
lblResult.Text = "文件不能超过4M!";
return;
}
else
{
lblResult.Text = "";
}
//将要上传的文件存入ArrayList和Session中
arraylist.Add(this.FileUpload1.PostedFile);
Session["UPLOAD"] = arraylist;
}
else
{
lblResult.Text = "请选择上传文件!";
}
}
else if (Session["UPLOAD"] != null)
{
//检查是否有文件要上传
if (this.FileUpload1.HasFile)
{
if (this.FileUpload1.PostedFile.ContentLength > 4096000)
{
lblResult.Text = "文件不能超过4M!";
return;
}
else
{
lblResult.Text = "";
}
arraylist = Session["UPLOAD"] as ArrayList;
//将要上传的文件存入ArrayList和Session中
arraylist.Add(this.FileUpload1.PostedFile);
Session["UPLOAD"] = arraylist;
}
else
{
lblResult.Text = "请选择上传文件!";
}
}
//绑定DataList
DataList1.DataSource = Session["UPLOAD"];
DataList1.DataBind();
}
/// <summary>
/// 上传按钮
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param> n,
protected void btnUpload_Click(object sender, EventArgs e)
{
string strPath = Server.MapPath("~/files/");
if (Session["UPLOAD"] != null)
{
//从ArrayList中取出要上传的文件
ArrayList list = Session["UPLOAD"] as ArrayList;
for (int i = 0; i < list.Count; i++)
{
HttpPostedFile PostedFile = list[i] as HttpPostedFile;
//将文件上传到指定路径
PostedFile.SaveAs(strPath + System.IO.Path.GetFileName(PostedFile.FileName));
}
lblResult.Text = "上传成功!";
}
//上传后清空上传文件列表
if (CheckBox1.Checked)
{
Session["UPLOAD"] = null;
DataList1.DataSource = Session["UPLOAD"];
DataList1.DataBind();
}
}
}
前台代码：
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" Debug="true"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>无标题页</title>
</head>
<body>
<center>
<h2>
</h2>
<form id="form1" runat="server">
<div>
<asp:Label ID="Label1" runat="server" Style="font-weight: bold; font-size: x-large"
Text="文件上传操作示例"></asp:Label>
</div>
<table border="1" style="width: 676px; height: 197px">
<tr>
<td colspan="3">
<asp:FileUpload ID="FileUpload1" runat="server" Width="404px" Height="29px" /></td>
</tr>
<tr>
<td colspan="3" rowspan="2">
<asp:Label ID="lblResult" runat="server" ForeColor="Red"></asp:Label></td>
</tr>
<tr>
</tr>
<tr>
<td colspan="2" rowspan="1" style="width: 2503px; height: 25px;" align="center">
<asp:Button ID="btnAdd" runat="server" Text="增 加" OnClick="btnAdd_Click" /></td>
<td colspan="1" rowspan="1" align="center" style="height: 25px">
<asp:Button ID="btnUpload" runat="server" OnClick="btnUpload_Click" Text="上 传" /></td>
</tr>
<tr>
<td align="center" colspan="3" rowspan="1">
<asp:CheckBox ID="CheckBox1" runat="server" Text="上传后清空上传文件列表" AutoPostBack="True" /></td>
</tr>
<tr>
<td colspan="3" rowspan="2">
<asp:DataList ID="DataList1" runat="server" CellPadding="3" Height="1px" Width="615px" BackColor="White" BorderColor="#E7E7FF" BorderStyle="None" BorderWidth="1px" GridLines="Horizontal">
<FooterStyle BackColor="#B5C7DE" ForeColor="#4A3C8C" />
<SelectedItemStyle BackColor="#738A9C" Font-Bold="True" ForeColor="#F7F7F7" />
<AlternatingItemStyle BackColor="#F7F7F7" />
<ItemStyle BackColor="#E7E7FF" ForeColor="#4A3C8C" />
<HeaderStyle BackColor="#4A3C8C" Font-Bold="True" ForeColor="#F7F7F7" />
<ItemTemplate>
<table style="width: 419px; height: 54px">
<tr>
<td>
文件名称：</td>
<td style="width: 288px">
<asp:Label ID="lblName" runat="server" Text='<%# Eval("FileName") %>'></asp:Label></td>
</tr>
<tr>
<td>
文件大小：</td>
<td style="width: 288px">
<asp:Label ID="lblLength" runat="server" Text='<%# Eval("ContentLength") %>'></asp:Label></td>
</tr>
<tr>
<td style="height: 20px">
文件类型：</td>
<td style="width: 288px; height: 20px;">
<asp:Label ID="lblType" runat="server" Text='<%# Eval("ContentType") %>'></asp:Label></td>
</tr>
</table>
</ItemTemplate>
<HeaderTemplate>
上传文件列表
</HeaderTemplate>
</asp:DataList> </td>
</tr>
<tr>
</tr>
</table>
</form>
</center>
</body>
</html>