C# 使用WebClient下载文件到本地目录

1、配置本地目录路

<appSettings>  <!--文件下载目录-->  <add key="Download_Dic" value="E:MyDownloadFile"/></appSettings>

2、创建FileHandler.cs类，编写下载代码

/// <summary>/// 文件处理类/// </summary>public static class FileHandler{    /// <summary>    /// 文件下载目录    /// </summary>    private static string _directory = @ConfigurationSettings.AppSettings["Download_Dic"];     /// <summary>    /// 下载文件    /// </summary>    /// <param name="url">下载地址</param>    /// <returns>文件名称</returns>    public static string DownloadFile(string url)    {        try        {            string fileName = CreateFileName(url);            if (!Directory.Exists(_directory))            {                Directory.CreateDirectory(_directory);            }            WebClient client = new WebClient();            client.DownloadFile(url, _directory + fileName);            return fileName;        }        catch        {            return "";        }    }     /// <summary>    /// 创建文件名称    /// </summary>    public static string CreateFileName(string url)    {        string fileName = "";        string fileExt = url.Substring(url.LastIndexOf(".")).Trim().ToLower();        Random rnd = new Random();        fileName = DateTime.Now.ToString("yyyyMMddHHmmssfff") + rnd.Next(10, 99).ToString() + fileExt;        return fileName;    } }

3、调用测试

static void Main(string[] args){    string url = "https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1494677827304&di=8e8aaf1a717ae37b73b772ee4728c7ea&imgtype=0&src=http%3A%2F%2Fscimg.jb51.net%2Fallimg%2F141123%2F10-1411231F92W16.jpg";    string fileName = FileHandler.DownloadFile(url);    if (!String.IsNullOrEmpty(fileName))    {        Console.WriteLine("文件下载成功，文件名称：" + fileName);    }    else    {        Console.WriteLine("文件下载失败");    }        Console.ReadLine();}