文件下载的一个类[原创]

王朝asp·作者佚名  2006-01-09
窄屏简体版  字體: |||超大  

/// <summary>

/// 下载文件

/// </summary>

public class BDDownLoadFile

{

private string Url; //要下载的文件URL地址

private string SavePath; //要保存的文件的目录

private string errMsg; //保存错误信息

private string RegValue = @"+.)+[w-]+(/[w]http://([w-]+.)+[w-]+(/[w- ./?%&=]*)?";

private string SaveFile; //生成的文件

public BDDownLoadFile(string url,string path)

{

Url = url;

SavePath = path;

this.SaveFile = GetFileName();

}

/// <summary>

/// 返回错误信息

/// </summary>

public string ErrorMessage

{

get

{

return this.errMsg;

}

}

public string GetSaveFile

{

get

{

return this.SaveFile;

}

}

public bool DownLoadFile()

{

bool result = true;

if( !CheckUrl(this.Url) )

{

this.errMsg = "网址不合法!";

return false;

}

WebClient objWC = new WebClient();

objWC.Credentials = CredentialCache.DefaultCredentials;

try

{

byte[] tmpData = objWC.DownloadData(this.Url);

if(tmpData.Length > 0)

{

FileStream objFS = new FileStream(this.SaveFile,FileMode.Create);

objFS.Write(tmpData,0,(int)tmpData.Length); //向文件写入数据

objFS.Close();

this.errMsg = "有数据!";

}

else

{

result = false;

this.errMsg = "没有接收到任何数据!";

}

}

catch(System.Net.WebException e)

{

this.errMsg += "<li>下载数据时发生错误!" + e.Message;

return false;

}

catch(System.UriFormatException e)

{

this.errMsg += "<li>访问的网址无效!" + e.Message;

return false;

}

catch(Exception e)

{

this.errMsg = "错误信息:<li>."+e.Message;

result = false;

}

finally

{

objWC.Dispose();

}

return result;

}

/// <summary>

/// 检查网址是否合法

/// </summary>

/// <param name="chkUrl">要检查的网址</param>

/// <returns></returns>

private bool CheckUrl(string chkUrl)

{

Regex reg = new Regex(RegValue);

Match match = reg.Match(chkUrl);

return match.Success;

}

/// <summary>

/// 取得网址是否有文件,如果有文件,则处理,若没有,则返回.html

/// </summary>

/// <param name="chkUrl"></param>

/// <returns></returns>

private string GetFileType(string chkUrl)

{

if(chkUrl.LastIndexOf("/") == (chkUrl.Length-1)) //没有具体文件

return "html";

int j = 0;

for(int i = 0; i < chkUrl.Length; i++)

{

if(chkUrl.IndexOf("/",i)>-1)

{

i = chkUrl.IndexOf("/",i);

j++;

}

}

if( j < 3)

return "html";

//取得"/"后的字符,然后得出文件类型

string end = chkUrl.Substring(chkUrl.LastIndexOf(".")+1);

switch(end)

{

case "asp":

case "aspx":

case "jsp":

case "php":

return "html";

default:

return end;

}

}

private string GetFileName()

{

string fileName = this.SavePath + "\\" + System.DateTime.Now.Year.ToString()+System.DateTime.Now.Month.ToString()+System.DateTime.Now.Day.ToString()+System.DateTime.Now.Minute.ToString()+System.DateTime.Now.Second.ToString()+Common.MakeRandom(4).ToString()+"."+GetFileType(this.Url);

for(;File.Exists(fileName);)

{

fileName = this.SavePath + "\\" + System.DateTime.Now.Year.ToString()+System.DateTime.Now.Month.ToString()+System.DateTime.Now.Day.ToString()+System.DateTime.Now.Minute.ToString()+System.DateTime.Now.Second.ToString()+Common.MakeRandom(4).ToString()+"\"+GetFileType(this.Url);

}

return fileName;

}

} //BDDownLoadFile end

 
 
 
免责声明:本文为网络用户发布,其观点仅代表作者个人观点,与本站无关,本站仅提供信息存储服务。文中陈述内容未经本站证实,其真实性、完整性、及时性本站不作任何保证或承诺,请读者仅作参考,并请自行核实相关内容。
 
 
© 2005- 王朝網路 版權所有 導航