下载前1000字节

Question

我需要使用C＃从互联网下载文本文件。文件大小可能相当大，我需要的信息总是在前1000个字节内。这可能吗？

Answer 1

从here盗窃。

string GetWebPageContent(string url) 
{ 
    string result = string.Empty; 
    HttpWebRequest request; 
    const int bytesToGet = 1000; 
    request = WebRequest.Create(url) as HttpWebRequest; 

    //get first 1000 bytes 
    request.AddRange(0, bytesToGet - 1); 

    // the following code is alternative, you may implement the function after your needs 
    using (WebResponse response = request.GetResponse()) 
    { 
     using (Stream stream = response.GetResponseStream()) 
     { 
      byte[] buffer = new byte[1024]; 
      int read = stream.Read(buffer, 0, 1000); 
      Array.Resize(ref buffer, read); 
      return Encoding.ASCII.GetString(buffer); 
     } 

    } 
} 

（编辑为在评论...要求;））

Answer 2

我这样做是为解答您的问题更新。如果你愿意，你也可以把范围标题放在里面，但是我排除了它。

string GetWebPageContent(string url) 
    { 
     //string result = string.Empty; 
     HttpWebRequest request; 
     const int bytesToGet = 1000; 
     request = WebRequest.Create(url) as HttpWebRequest; 
     var buffer = new char[bytesToGet]; 
     using (WebResponse response = request.GetResponse()) 
     { 
      using (StreamReader sr = new StreamReader(response.GetResponseStream())) 
      { 
       sr.Read(buffer, 0, bytesToGet); 
      } 
     } 
     return new string(buffer); 
    }