目录
1.get请求方式
1.1不需要请求参数时
1.2请求参数可以用表单数据(键值对)拼接时
2.POST请求方式
2.1请求参数为json字符串格式时
2.2请求参数为表单数据(键值对)格式时
2.3请求参数为多分部数据(复合式表单)格式时，(以上传文件接口为例)
本文主要介绍了通过C#中的WebRequest来发送post和get两种请求方式的过程。
1.get请求方式
1.1不需要请求参数时
url为请求的接口地址
private string GetData(string url){string result = string.Empty;string error = string.Empty;try{HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);request.Timeout = 20000; //超时时间request.Method = "GET"; //请求方式request.KeepAlive = true; //解决GetResponse操作超时问题request.Headers.Add("Authorization", "token"); //如果接口需要鉴权, 把"token"换成自己需要的//通过HttpWebRequest的GetResponse()方法建立HttpWebResponse,强制类型转换HttpWebResponse response = (HttpWebResponse)request.GetResponse();//获取响应内容，返回的数据格式: {"status":"success","msg":"成功","data":{"info": "example"}}string postContent = new StreamReader(response.GetResponseStream()).ReadToEnd();//结果解析,异常情况判断JObject json = JObject.Parse(postContent);var gList = json["data"];if (json["status"] == null || gList == null || json["msg"] == null)error = "接口错误";else if (json["status"].ToString() != "success")error = string.Format("接口查询结果返回错误,{0}", json["msg"]);else if (gList.ToString() != string.Empty)result = gList["info"].ToString();else { }}catch (Exception ex){error = ex.Message;}if (error != string.Empty)MessageBox.Show(error);return result;}
1.2请求参数可以用表单数据(键值对)拼接时
url为请求的接口地址，pairs为请求的参数(字典格式)
private string GetUrlEncodeData(string url, Dictionary<string, string> pairs){string result = string.Empty;string error = string.Empty;try{StringBuilder sb = new StringBuilder();foreach (string key in pairs.Keys)sb.Append(key).Append("=").Append(pairs[key]).Append("&");if (pairs.Count > 0)url = url + "?" + sb.ToString().Trim('&');HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);request.ContentType = "application/x-www-form-urlencoded"; //表单数据(键值对)request.Timeout = 20000; //超时时间request.Method = "GET"; //请求方式request.KeepAlive = true; //解决GetResponse操作超时问题request.Headers.Add("Authorization", "token"); //如果接口需要鉴权, 把"token"换成自己需要的//通过HttpWebRequest的GetResponse()方法建立HttpWebResponse,强制类型转换HttpWebResponse response = (HttpWebResponse)request.GetResponse();//获取响应内容，返回的数据格式: {"status":"success","msg":"成功","data":{"info": "example"}}string postContent = new StreamReader(response.GetResponseStream()).ReadToEnd();//结果解析,异常情况判断JObject json = JObject.Parse(postContent);var gList = json["data"];if (json["status"] == null || gList == null || json["msg"] == null)error = "接口错误";else if (json["status"].ToString() != "success")error = string.Format("接口查询结果返回错误,{0}", json["msg"]);else if (gList.ToString() != string.Empty)result = gList["info"].ToString();else { }}catch (Exception ex){error = ex.Message;}if (error != string.Empty)MessageBox.Show(error);return result;}
2.POST请求方式
2.1请求参数为json字符串格式时
url为请求的接口地址，pairs为请求的参数(字典格式)
private string PostJsonData(string url, Dictionary<string, string> pairs){string result = string.Empty;string error = string.Empty;try{HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);request.Timeout = 20000; //超时时间request.Method = "POST"; //请求方式request.KeepAlive = true; //解决GetResponse操作超时问题request.Headers.Add("Authorization", "token"); //如果接口需要鉴权, 把"token"换成自己需要的//设置Content-type HTTP标头的值，即请求的媒体类型request.ContentType = "application/json"; //json字符串//request.ContentType = "multipart/form-data"; //多分部数据string content = JsonConvert.SerializeObject(pairs);byte[] data = Encoding.UTF8.GetBytes(content);//写入请求的参数using (var stream = request.GetRequestStream())stream.Write(data, 0, data.Length);//通过HttpWebRequest的GetResponse()方法建立HttpWebResponse,强制类型转换HttpWebResponse response = (HttpWebResponse)request.GetResponse();//获取响应内容，返回的postContent是json字符串格式:{"status":"success","msg":"成功","data":{"info": "example"}}string postContent = new StreamReader(response.GetResponseStream()).ReadToEnd();//结果解析,异常情况判断JObject json = JObject.Parse(postContent);var gList = json["data"];if (json["status"] == null || gList == null || json["msg"] == null)error = "接口错误";else if (json["status"].ToString() != "success")error = string.Format("接口查询结果返回错误,{0}", json["msg"]);else if (gList.ToString() != string.Empty)result = gList["info"].ToString();else { }}catch (Exception ex){error = ex.Message;}if (error != string.Empty)MessageBox.Show(error);return result;}
2.2请求参数为表单数据(键值对)格式时
url为请求的接口地址，pairs为请求的参数(字典格式)
private string PostUrlEncodeData(string url, Dictionary<string, string> pairs){string result = string.Empty;string error = string.Empty;try{HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);request.ContentType = "application/x-www-form-urlencoded"; //表单数据(键值对)request.Timeout = 20000; //超时时间request.Method = "POST"; //请求方式request.KeepAlive = true; //解决GetResponse操作超时问题request.Headers.Add("Authorization", "token"); //如果接口需要鉴权, 把"token"换成自己需要的StringBuilder sb = new StringBuilder();foreach (string key in pairs.Keys)sb.Append(key).Append("=").Append(pairs[key]).Append("&");string content = sb.ToString().Trim('&');byte[] data = Encoding.UTF8.GetBytes(content);//写入请求的参数using (var stream = request.GetRequestStream())stream.Write(data, 0, data.Length);//通过HttpWebRequest的GetResponse()方法建立HttpWebResponse,强制类型转换HttpWebResponse response = (HttpWebResponse)request.GetResponse();//获取响应内容，返回的json字符串postContent格式: //{"status":"success","msg":"成功","data":{"info": "example"}}string postContent = new StreamReader(response.GetResponseStream()).ReadToEnd();//结果解析,异常情况判断JObject json = JObject.Parse(postContent);var gList = json["data"];if (json["status"] == null || gList == null || json["msg"] == null)error = "接口错误";else if (json["status"].ToString() != "success")error = string.Format("接口查询结果返回错误,{0}", json["msg"]);else if (gList.ToString() != string.Empty)result = gList["info"].ToString();else { }}catch (Exception ex){error = ex.Message;}if (error != string.Empty)MessageBox.Show(error);return result;}
2.3请求参数为多分部数据(复合式表单)格式时，(以上传文件接口为例)
url为请求的接口地址，filePath为文件的绝对路径。
首先获取本地文件路径，
string uploadURL = "http://127.0.0.1:8888/api/test/";string uploadFilePath = string.Empty;OpenFileDialog openFileDialog = new OpenFileDialog{Filter = "所有文件|*.*"};if (openFileDialog.ShowDialog() == DialogResult.OK)uploadFilePath = openFileDialog.FileName;string result = PostMultipartData(uploadURL, uploadFilePath);
上传文件函数
private string PostMultipartData(string url, string filePath){string result = string.Empty;string error = string.Empty;try{HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);request.Timeout = 20000; //超时时间request.Method = "POST"; //请求方式request.KeepAlive = true; //解决GetResponse操作超时问题request.ContentType = "multipart/form-data"; //多分部数据(复合式表单)request.Headers.Add("Authorization", "token"); //如果接口需要鉴权, 把"token"换成自己需要的//读取文件内容FileStream fs = new FileStream(filePath, FileMode.Open, FileAccess.Read);byte[] fileData = new byte[fs.Length];fs.Read(fileData, 0, fileData.Length);string fileName = Path.GetFileName(filePath);//浏览器在发送表单的enctype="multipart/form-data", 需要在往后台发送请求的时候添加一个[boundary]属性string boundary = "test" + DateTime.Now.Ticks.ToString("x"); // 边界符, "test"可以改, 其他部分不能改byte[] boundarybytes = Encoding.UTF8.GetBytes("\r\n--" + boundary + "\r\n"); // 边界符开始byte[] endbytes = Encoding.UTF8.GetBytes("\r\n--" + boundary + "--\r\n"); // 边界符结束//写入请求的参数using (var stream = request.GetRequestStream()){//获取文件头的字节序列string temp = "Content-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\n";string header = string.Format(temp, "file", fileName);byte[] fileHeader = Encoding.UTF8.GetBytes(header);stream.Write(boundarybytes, 0, boundarybytes.Length); //写入FormData项的开始边界符stream.Write(fileHeader, 0, fileHeader.Length); //将文件头写入FormData项中stream.Write(boundarybytes, 0, boundarybytes.Length); //每两次写入之间要加入开始边界符stream.Write(fileData, 0, fileData.Length); //将文件流写入FormData项stream.Write(endbytes, 0, endbytes.Length); //写入FormData的结束边界符}//通过HttpWebRequest的GetResponse()方法建立HttpWebResponse,强制类型转换HttpWebResponse response = (HttpWebResponse)request.GetResponse();//获取响应内容，返回的json字符串postContent格式: //{"status":"success","msg":"成功","data":{"info": "example"}}string postContent = new StreamReader(response.GetResponseStream()).ReadToEnd();//结果解析,异常情况判断JObject json = JObject.Parse(postContent);var gList = json["data"];if (json["status"] == null || gList == null || json["msg"] == null)error = "接口错误";else if (json["status"].ToString() != "success")error = string.Format("接口查询结果返回错误,{0}", json["msg"]);else if (gList.ToString() != string.Empty)result = gList["info"].ToString();else { }}catch (Exception ex){error = ex.Message;}if (error != string.Empty)MessageBox.Show(error);return result;}
