ASP.NET中常用的附件上传下载

在NET项目中，常常会遇到附件上传下载功能的开发，这里把我的代码分享给大家，希望对大家有帮助，同时也希望大虾们能予以指点。

1.新建用户控件UC_Attachment.ascx

<%@ Control Language="C#" AutoEventWireup="true" CodeBehind="UC_Attachment.ascx.cs" Inherits="DH.WorkFlow.Platform.WorkSpace.WebControls.UC_Attachment" %>
<table style="800px; background-color:#D2D2D2; text-align:left;" align="center" cellpadding="0" cellspacing="1">
    <tr style="height:25px; background-color:#EEEEEE;">
        <td style="500px;">&nbsp;附件名称</td>
        <td style="140px;">&nbsp;上传人</td>
        <td style="100px;">&nbsp;上传时间</td>
        <td style="60px;">&nbsp;操作</td>
    </tr>
    <asp:Repeater ID="rptAttachment" runat="server" OnItemCommand="rptAttachment_ItemCommand" >
        <ItemTemplate>
        <tr style="height:25px; background-color:#FFFFFF;">
            <td><a href='/Images/DownloadAttachment.aspx?FileReName=<%# Eval("AttReName") %>' target="_blank">&nbsp;<%# Eval("AttName") %></a></td>
            <td>&nbsp;<%# Eval("UploadBy") %></td>
            <td>&nbsp;<%# Eval("UploadDate") %></td>
            <td>&nbsp;<asp:LinkButton ID="lbDeleteAtt" runat="server" Text="删除" CommandName="DeleAtt" ></asp:LinkButton></td>
        </tr>
        </ItemTemplate>
    </asp:Repeater>
</table>

<table style="800px; background-color:#FFFFFF; text-align:left;" align="center" cellpadding="0" cellspacing="0">
    <tr>
        <td>（提示：单个文件须小于10M ！）</td>
        <td align="right" height="25px">
            <asp:FileUpload ID="FileUpload1" runat="server" Width="300px" BorderStyle="Solid" BorderWidth="1px" />&nbsp;
            <asp:Button ID="AddAttachment" runat="server" Text="上  传" CssClass="button2" onclick="AddAttachment_Click" />
        </td>
    </tr>
</table>

2.用户控件的CS文件UC_Attachment.ascx.cs代码如下

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.IO;
using System.Data;

namespace DH.WorkFlow.Platform.WorkSpace.WebControls
{
    public partial class UC_Attachment : System.Web.UI.UserControl
    {
        public DataTable AttachmentTable
        {
            get
            {
                if (ViewState["AttachmentTable"] != null)
                {
                    return ViewState["AttachmentTable"] as DataTable;
                }
                else
                {
                    DataTable dt = new DataTable();
                    dt.Columns.Add("AttName");
                    dt.Columns.Add("AttReName");
                    dt.Columns.Add("UploadBy");
                    dt.Columns.Add("UploadDate");
                    dt.Columns.Add("AttFullPath");
                    dt.Columns.Add("AttRemarks");
                    return dt;
                }
            }
            set { ViewState["AttachmentTable"] = value; }
        }

        protected void Page_Load(object sender, EventArgs e)
        {

        }

        #region 上传附件
        protected void AddAttachment_Click(object sender, EventArgs e)
        {
            int fileLength = FileUpload1.PostedFile.ContentLength;
            string fileName = FileUpload1.FileName;
            string fileType = fileName.Substring(fileName.LastIndexOf('.') + 1, FileUpload1.FileName.Length - fileName.LastIndexOf('.') - 1);
            string[] arrTypes = new string[] { "chm", "doc", "docx", "txt", "text", "png", "mht", "xls", "xlsx", "ppt", "pptx", "jpg", "gif" };
            if (fileLength < 0)
            {
                AlertMessage("上传文件为空或者文件大小为0！", string.Empty);
                return;
            }
            if (fileLength > (10 * 1024 * 1024))
            {
                AlertMessage("上传文件必须小于10M！", string.Empty);
                return;
            }
            if (!arrTypes.Contains(fileType))
            {
                AlertMessage("上传文件格式有误！", string.Empty);
                return;
            }

            try
            {
                string uploadPath = System.Configuration.ConfigurationManager.AppSettings["UploadPath"];
                if (!Directory.Exists(uploadPath))
                    Directory.CreateDirectory(uploadPath);
                string strReFileName = DateTime.Now.ToString("yyMMddHHmmssfff") + FileUpload1.FileName;
                string strFileFullPath = uploadPath + strReFileName;
                FileUpload1.SaveAs(strFileFullPath);

                using (DataTable dt = GetAttachmentTable())
                {
                    DataRow row = dt.NewRow();
                    row["AttName"] = FileUpload1.FileName;
                    row["AttReName"] = strReFileName;
                    row["UploadBy"] = DH.WF.BaseFramework.Organizations.Employee.Current.NameWithDomainName;
                    row["UploadDate"] = DateTime.Now.ToString("yyyy-MM-dd");
                    row["AttFullPath"] = strFileFullPath;
                    row["AttRemarks"] = string.Empty;
                    dt.Rows.Add(row);
                    BindAttachment(dt);
                }
            }
            catch (Exception ex)
            {
                AlertMessage("文件上传过程中出现错误：" + ex.Message, string.Empty);
            }
        }
        private DataTable GetAttachmentTable()
        {
            return AttachmentTable;
        }
        private void BindAttachment(DataTable dt)
        {
            AttachmentTable = dt;

            rptAttachment.DataSource = dt;
            rptAttachment.DataBind();
        }
        protected void rptAttachment_ItemCommand(object sender, RepeaterCommandEventArgs e)
        {
            if (e.CommandName == "DeleAtt")
            {
                using (DataTable dt = GetAttachmentTable())
                {
                    DataRow row = dt.Rows[e.Item.ItemIndex];
                    string strFileFullPath = row["AttFullPath"].ToString();
                    if (File.Exists(strFileFullPath))
                        File.Delete(strFileFullPath);

                    dt.Rows.RemoveAt(e.Item.ItemIndex);
                    BindAttachment(dt);
                }
            }
        }
        #endregion

        private void AlertMessage(string strMsg, string strUrl)
        {
            if (string.IsNullOrEmpty(strUrl))
                this.Page.ClientScript.RegisterStartupScript(GetType(), "alert", "<script>alert('" + strMsg.Replace("\r\n", "<br />").Replace(" ", "&nbsp;") + "');</script>");
            else
                this.Page.ClientScript.RegisterStartupScript(GetType(), "alert", "<script>alert('" + strMsg.Replace("\r\n", "<br />").Replace(" ", "&nbsp;") + "');window.location.href='" + strUrl + "';</script>");
        }

    }
}

3.下载页面DownloadAttachment.aspx

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="DownloadAttachment.aspx" %>

<!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></title>
    <script runat="server">
    protected void Page_Load(object sender, EventArgs e)
    {
        string agrFileReName = Request.QueryString["FileReName"] != null ? Request.QueryString["FileReName"] : "";
        string uploadPath = System.Configuration.ConfigurationManager.AppSettings["UploadPath"];
        string fileFullPath = uploadPath + agrFileReName;
        if (!string.IsNullOrEmpty(agrFileReName))
        {
            System.IO.FileInfo fi = new System.IO.FileInfo(fileFullPath);
            Response.Clear();
            Response.Charset = "GB2312";
            Response.ContentEncoding = System.Text.Encoding.UTF8;
            // 添加头信息，为"文件下载/另存为"对话框指定默认文件名
            Response.AddHeader("Content-Disposition", "attachment; filename=" + Server.UrlEncode(agrFileReName));
            // 添加头信息，指定文件大小，让浏览器能够显示下载进度
            Response.AddHeader("Content-Length", fi.Length.ToString());
            // 指定返回的是一个不能被客户端读取的流，必须被下载
            Response.ContentType = "application/ms-excel";
            // 把文件流发送到客户端
            Response.WriteFile(fi.FullName);
            // 停止页面的执行
            //Response.End();     
            HttpContext.Current.ApplicationInstance.CompleteRequest();
        }
    }
    </script>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    
    </div>
    </form>
</body>
</html>