HttpWebRequest POST请求webapi：如果参数是简单类型，比如字符串（注意，拼接的字符串要HttpUtility.UrlEncode才行，否则服务端会丢失特殊字符&后面的数据）
要点：如下代码统一设置为：ContentType = "application/x-www-form-urlencoded";
服务端代码1：URL格式为
public string Post([FromBody] string value)
则客户端Post的数据：拼接的字符串必须以 =开头，否则服务端无法取得value。例如：=rfwreewr2332322232 或者 {
'':value}
服务端代码2：URL格式为 ?value={value}
public string Post(string value)
则客户端Post的数据：需要url里拼接出KeyValue这样的数据
服务端代码3：URL格式为
public string Post()
则客户端Post的数据：无要求。例如：key=rfwreewr2332322232。
服务端：可以用HttpContext.Current.Request.InputStream或者HttpContext.Current.Request.Form[0]都可以获取
如果post的参数类型比较复杂，则需要自定义类
要点：如下代码统一设置为：ContentType = "application/json";
服务端代码1：URL格式为
public string Post([FromBody] Model value)或者 public string Post(Model value)
则客户端Post的数据：{\"id\":\"test1\",\"name\":\"value\"}。服务端会自动映射到对象。
提交代码如下：
HttpWebRequest wReq = (HttpWebRequest)WebRequest.Create("http://localhost:37831/api/Values"); wReq.Method = "Post"; //wReq.ContentType = "application/json"; //wReq.ContentType = "application/x-www-form-urlencoded"; wReq.ContentType = "application/json"; //byte[] data = Encoding.Default.GetBytes(HttpUtility.UrlEncode("key=rfwreewr2332322232&261=3&261=4")); byte[] data = Encoding.Default.GetBytes("{\"id\":\"test1\",\"name\":\"value\"}"); wReq.ContentLength = data.Length; Stream reqStream = wReq.GetRequestStream(); reqStream.Write(data, 0, data.Length); reqStream.Close(); using (StreamReader sr = new StreamReader(wReq.GetResponse().GetResponseStream())) { string result = sr.ReadToEnd(); } 服务段代码如下：
// POST api/values //public string Post() //{ // FileInfo fi = new FileInfo(AppDomain.CurrentDomain.BaseDirectory + "log.txt"); // StreamWriter sw = fi.CreateText(); // StreamReader sr = new StreamReader(HttpContext.Current.Request.InputStream); // sw.WriteLine("1:" + sr.ReadToEnd()+"--"+ HttpContext.Current.Request.Form[0]); // sw.Flush(); // sw.Close(); // return "{\"test\":\"1\"}"; //} // POST api/values public HttpResponseMessage PostStudent(Student student) { FileInfo fi = new FileInfo(AppDomain.CurrentDomain.BaseDirectory + "log.txt"); StreamWriter sw = fi.AppendText(); sw.WriteLine("2:" + student.id); sw.Flush(); sw.Close(); HttpResponseMessage result = new HttpResponseMessage { Content = new StringContent("{\"test\":\"2\"}", Encoding.GetEncoding("UTF-8"), "application/json") }; return result; }