实例详解C#实现http不同方法的请求

1、不带参数的POST请求

public static string Post(string url)
{
  string result = "";
  HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);
  req.Method = "POST";
  HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
  Stream stream = resp.GetResponseStream();
  //获取内容
  using (StreamReader reader = new StreamReader(stream, Encoding.UTF8))
  {
    result = reader.ReadToEnd();
  }
  return result;
} 

2、带参数的POST请求

public static string Post(string url,Dictionary<string,string> dic)
{
  string result = "";
  HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);
  req.Method = "POST";
  req.ContentType = "application/x-www-form-urlencoded";
  #region 添加Post 参数
  StringBuilder builder = new StringBuilder();
  int i = 0;
  foreach (var item in dic)
  {
    if (i > 0)
      builder.Append("&");
    builder.AppendFormat("{0}={1}", item.Key, item.Value);
    i++;
  }
  byte[] data = Encoding.UTF8.GetBytes(builder.ToString());
  req.ContentLength = data.Length;
  using (Stream reqStream = req.GetRequestStream())
  {
    reqStream.Write(data, 0, data.Length);
    reqStream.Close();
  }
  #endregion
  HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
  Stream stream = resp.GetResponseStream();
  //获取响应内容
  using (StreamReader reader = new StreamReader(stream, Encoding.UTF8))
  {
    result = reader.ReadToEnd();
  }
  return result;
} 

3、不带参数的GET请求

public static string Get(string url)
{
  string result = "";
  HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);
  HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
  Stream stream = resp.GetResponseStream();
  try
  {
    //获取内容
    using (StreamReader reader = new StreamReader(stream))
    {
      result = reader.ReadToEnd();
    }
  }
  finally
  {
    stream.Close();
  }
  return result;
} 

4、带参数的GET请求

public static string Get(string url, Dictionary<string, string> dic)
{
  string result = "";
  StringBuilder builder = new StringBuilder();
  builder.Append(url);
  if (dic.Count > 0)
  {
    builder.Append("?");
    int i = 0;
    foreach (var item in dic)
    {
      if (i > 0)
        builder.Append("&");
      builder.AppendFormat("{0}={1}", item.Key, item.Value);
      i++;
    }
  }
  HttpWebRequest req = (HttpWebRequest)WebRequest.Create(builder.ToString());
  //添加参数
  HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
  Stream stream = resp.GetResponseStream();
  try
  {
    //获取内容
    using (StreamReader reader = new StreamReader(stream))
    {
      result = reader.ReadToEnd();
    }
  }
  finally
  {
    stream.Close();
  }
  return result;
} 

5、自定义HTTP请求头

HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);
req.Method = "GET";
req.Headers["Accept-Language"] = "zh-CN,zh;q=0.8";
req.Referer = "https://www.baidu.com/";
HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
Stream stream = resp.GetResponseStream(); string result = ""; //注意，此处使用的编码是：gb2312 //using (StreamReader reader = new StreamReader(stream, Encoding.Default)) using (StreamReader reader = new StreamReader(stream, Encoding.GetEncoding("gb2312")))
{
  result = reader.ReadToEnd();
}