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  • ASP.NET(C#)FileUpload实现上传限定类型和大小的文件到服务器

    上传文件有两个主要的目的地,一个是服务器,另一个是数据库,ASP.NET内置了FileUpload这个上传控件,文本框显示用户选择的文件的全名.

    其属性主要包括:

    ContenLength:上传文件大小,单位:字节

    FileName:文件名称

    HasFile:是否选择了文件


    例子:
    测试环境.net 2.0(内有详细说明)

    default.aspx
    <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>

    <!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>
    <form id="form1" runat="server">
    <div>
    <asp:FileUpload ID="FileUpload1" runat="server" /><br />
    <br />
    <asp:Button ID="btnUpload" runat="server" OnClick="btnUpload_Click" Text="上传" /> </div>
    </form>
    </body>
    </html>

    default.aspx.cs

    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;

    public partial class _Default : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
          
        }
        protected void btnUpload_Click(object sender, EventArgs e)
        {
            Boolean fileOk = false;
            string path = Server.MapPath("~/upload/");
            //判断是否已经选取文件
            if (FileUpload1.HasFile)
            {
                //取得文件的扩展名,并转换成小写
                string fileExtension = System.IO.Path.GetExtension(FileUpload1.FileName).ToLower();
                //限定只能上传jpg和gif图片
                string[] allowExtension = { ".jpg", ".gif" };
                //对上传的文件的类型进行一个个匹对
                for (int i = 0; i < allowExtension.Length; i++)
                {
                    if (fileExtension == allowExtension[i])
                    {
                        fileOk = true;
                        break;
                    }
                }
                //对上传文件的大小进行检测,限定文件最大不超过1M
                if (FileUpload1.PostedFile.ContentLength > 1024000)
                {
                    fileOk = false;
                }
                //最后的结果
                if (fileOk)
                {
                    try
                    {
                        FileUpload1.SaveAs(path + System.DateTime.Now.ToString("yyyyMMddhhmmss"+FU.FileName);
                       Image.ImageUrl = "../Upload/" + System.DateTime.Now.ToString("yyyyMMddhhmmss") + FU.FileName;
                        Response.Write("<script type=‘text/javascript‘>window.alert(‘上传成功‘)</script>");
                    }
                    catch
                    {
                        Response.Write("<script type=‘text/javascript‘>window.alert(‘上传失败‘)</script>");
                    }
                }
                else
                {
                    Response.Write("<script type=‘text/javascript‘>window.alert(‘文件类型或者文件大小超出1M‘)</script>");
                }

            }
        }
    }

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  • 原文地址:https://www.cnblogs.com/juan/p/1441427.html
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