调用第三方API的时候要用到HttpWebRequest类发送HTTP请求，网上查阅一番后大致了解了该类的用法，现记录如下。
首先引入HttpWebRequest类，System.IO类
using HttpWebRequest
using System.IO
GET请求
/// <summary>
/// 发送GET请求
/// </summary>
/// <param name="url">请求URL，如果需要传参，在URL末尾加上“？+参数名=参数值”即可</param>
/// <returns></returns>
static string HttpGet(string url)
{
//创建
HttpWebRequest httpWebRequest = (HttpWebRequest)HttpWebRequest.Create(url);
//设置请求方法
httpWebRequest.Method = "GET";
//请求超时时间
httpWebRequest.Timeout = 20000;
//发送请求
HttpWebResponse httpWebResponse = (HttpWebResponse)httpWebRequest.GetResponse();
//利用Stream流读取返回数据
StreamReader streamReader = new StreamReader(httpWebResponse.GetResponseStream(), Encoding.UTF8);
//获得最终数据，一般是json
string responseContent = streamReader.ReadToEnd();
streamReader.Close();
httpWebResponse.Close();
return responseContent;
}
POST请求
/// <summary>
/// 发送POST请求
/// </summary>
/// <param name="url">请求URL</param>
/// <param name="data">请求参数</param>
/// <returns></returns>
static string HttpPost(string url, string data)
{
HttpWebRequest httpWebRequest = (HttpWebRequest)HttpWebRequest.Create(url);
//字符串转换为字节码
byte[] bs = Encoding.UTF8.GetBytes(data);
//参数类型，这里是json类型
//还有别的类型如"application/x-www-form-urlencoded"，不过我没用过(逃
httpWebRequest.ContentType = "application/json";
//参数数据长度
httpWebRequest.ContentLength = bs.Length;
//设置请求类型
httpWebRequest.Method = "POST";
//设置超时时间
httpWebRequest.Timeout = 20000;
//将参数写入请求地址中
httpWebRequest.GetRequestStream().Write(bs, 0, bs.Length);
//发送请求
HttpWebResponse httpWebResponse = (HttpWebResponse)httpWebRequest.GetResponse();
//读取返回数据
StreamReader streamReader = new StreamReader(httpWebResponse.GetResponseStream(), Encoding.UTF8);
string responseContent = streamReader.ReadToEnd();
streamReader.Close();
httpWebResponse.Close();
httpWebRequest.Abort();
return responseContent;
}
