准备工作：
建立.NET Core Web Api项目
新建一个用于Api请求的UserInfo类
public class UserInfo { public string name { get; set; } public int age { get; set; } public bool sex { get; set; } }
2、建立.NET Core Web项目
一、使用jQuery Ajax访问
（一）、表单 [FromForm]
数据类型：Object
ContenyType类型：application/x-www-form-urlencoded
var model = { name: "刘大大", age: 23, sex: true };
前台请求
var model = { name: "刘大大", age: 23, sex: true }; $.ajax({ url: "http://localhost:57954/API/Default/data", type: "POST", async: true, dataType: "json", data: model, contentType: "application/x-www-form-urlencoded", success: function (data) { console.log("data:"); console.log(data); } });
后台接受
（二）、JSON字符串 [FromBdy]
数据类型：Json
ContenyType类型：application/json
var json={"name":"刘大大","age":23,"sex":true}
也可以使用JSON.stringify(Object)将Object转换为JSON字符串
前端请求
var model = { name: "刘大大", age: 23, sex: true }; $.ajax({ url: "http://localhost:57954/API/Default/data", type: "POST", async: true, dataType: "json", data: JSON.stringify(model), contentType: "application/json", success: function (data) { console.log("data:"); console.log(data); } });
后台接受
（三）、文件上传
建立FormData对象
数据类型：FromData
ContenyType类型false, //必须false才会避开jQuery对 formdata 的默认处理
processData类型: false, //必须false才会自动加上正确的Content-Type
html
<input type="file" multiple id="file" />
JS获取文件对象
var file = document.getElementById("file"); var files = file.files; var formData = new FormData(); for (var i = 0; i < files.length; i++) { formData.append(files[i].name, files[i]); }
formData.append("name", "刘大大");//可追加参数
AJAX请求
$.ajax({ url: "http://localhost:57954/API/Default/data", type: "POST", async: true, dataType: "json", data: formData, contentType: false, processData: false, success: function (data) { console.log("data:"); console.log(data); } });
后台接受
追加的name参数
传输的文件
二、使用C#后台访问
（一）、Get访问
var url = "http://localhost:57954/API/Default/values";
using (var client = new HttpClient(new HttpClientHandler() { AutomaticDecompression = DecompressionMethods.Deflate | DecompressionMethods.GZip }))
{
var taskResponse = client.GetAsync(url);
taskResponse.Wait();
if (taskResponse.IsCompletedSuccessfully)
{
var taskStream = taskResponse.Result.Content.ReadAsStreamAsync();
taskStream.Wait();
using (var reader = new StreamReader(taskStream.Result))
{
jsonString = reader.ReadToEnd();
}
}
}
（二）、Post访问
var data = new {name="刘大大",age=23,sex=true }; using (var client = new HttpClient(new HttpClientHandler() { AutomaticDecompression = DecompressionMethods.Deflate | DecompressionMethods.GZip })) { var jsonToSend = JsonConvert.SerializeObject(data, Formatting.None, new IsoDateTimeConverter()); var body = new StringContent(jsonToSend, Encoding.UTF8, "application/json"); var taskResponse = client.PostAsync(url, body); taskResponse.Wait(); if (taskResponse.IsCompletedSuccessfully) { var taskStream = taskResponse.Result.Content.ReadAsStreamAsync(); taskStream.Wait(); using (var reader = new StreamReader(taskStream.Result)) { jsonString = reader.ReadToEnd(); } } }
（三）、上传文件
public IActionResult Upload() { var url = "http://localhost:57954/API/Default/values"; var data = new MultipartFormDataContent(); if (Request.HasFormContentType) { var request = Request.Form.Files; foreach (var item in request) { data.Add(new StreamContent(item.OpenReadStream()), item.Name, item.FileName); } foreach (var item in Request.Form) { data.Add(new StringContent(item.Value), item.Key); } } string jsonString; using (var client = new HttpClient(new HttpClientHandler() { AutomaticDecompression = DecompressionMethods.Deflate | DecompressionMethods.GZip })) { var taskResponse = client.PostAsync(url, data); taskResponse.Wait(); if (taskResponse.IsCompletedSuccessfully) { var taskStream = taskResponse.Result.Content.ReadAsStreamAsync(); taskStream.Wait(); using (var reader = new StreamReader(taskStream.Result)) { jsonString = reader.ReadToEnd(); } } } return Json("OK"); }
WebHelper
这里包含了WebRequest和HttpClient两种请求方式，以及包含了将Object对象序列化为HttpCotnent对象的方法。
/*************************************************************************************************************************************************** * *文件名：WebHelper.cs * *创建人：Jon * *日 期 ：2018年5月25日 * *描 述 ：实现HTTP协议中的GET、POST请求 * *MVC使用HttpClient上传文件实例： public IActionResult Upload() { var url = "http://localhost:57954/API/Default/values"; var data = new MultipartFormDataContent(); if (Request.HasFormContentType) { var request = Request.Form.Files; foreach (var item in request) { data.Add(new StreamContent(item.OpenReadStream()), item.Name, item.FileName); } foreach (var item in Request.Form) { data.Add(new StringContent(item.Value), item.Key); } } WebHelper.PostByHttpClientFromHttpContent(url, data); return Json("OK"); } *****************************************************************************************************************************************************/ using Newtonsoft.Json; using Newtonsoft.Json.Converters; using Newtonsoft.Json.Linq; using System; using System.Collections.Generic; using System.IO; using System.Net; using System.Net.Http; using System.Net.Http.Headers; using System.Text; namespace Expansion.Helper { public static class WebHelper { /// <summary> /// 通过WebRequest发起Get请求 /// </summary> /// <param name="url">请求地址</param> /// <returns>JSON字符串</returns> public static string GetByWebRequest(string url) { string jsonString = string.Empty; var request = (HttpWebRequest)WebRequest.Create(url); request.Method = "GET"; request.ContentType = "application/json"; request.AutomaticDecompression = DecompressionMethods.Deflate | DecompressionMethods.GZip; var response = (HttpWebResponse)request.GetResponse(); using (var stream = new StreamReader(response.GetResponseStream())) { jsonString = stream.ReadToEnd(); } return jsonString; } /// <summary> /// 通过WebRequest发起Post请求 /// </summary> /// <param name="url">请求地址</param> /// <param name="data">请求参数</param> /// <returns>JSON字符串</returns> public static string PostByWebRequest(string url, object data) { string jsonString = string.Empty; var request = (HttpWebRequest)WebRequest.Create(url); request.ContentType = "application/json"; request.Method = "POST"; request.Timeout = Int32.MaxValue; request.AutomaticDecompression = DecompressionMethods.Deflate | DecompressionMethods.GZip; var jsonToSend = JsonConvert.SerializeObject(data, Formatting.None, new IsoDateTimeConverter()); byte[] btBodys = Encoding.UTF8.GetBytes(jsonToSend); request.ContentLength = btBodys.Length; request.GetRequestStream().Write(btBodys, 0, btBodys.Length); var response = (HttpWebResponse)request.GetResponse(); using (var stream = new StreamReader(response.GetResponseStream())) { jsonString = stream.ReadToEnd(); } return jsonString; } /// <summary> /// 通过HttpClient发起Get请求 /// </summary> /// <param name="url">请求地址</param> /// <returns>JSON字符串</returns> public static string GetByHttpClient(string url) { string jsonString = string.Empty; using (var client = new HttpClient(new HttpClientHandler() { AutomaticDecompression = DecompressionMethods.Deflate | DecompressionMethods.GZip })) { var taskResponse = client.GetAsync(url); taskResponse.Wait(); if (taskResponse.IsCompletedSuccessfully) { var taskStream = taskResponse.Result.Content.ReadAsStreamAsync(); taskStream.Wait(); using (var reader = new StreamReader(taskStream.Result)) { jsonString = reader.ReadToEnd(); } } } return jsonString; } /// <summary> /// 通过HttpClient发起Post请求 /// </summary> /// <param name="url">请求地址</param> /// <param name="data">请求参数</param> /// <returns>JSON字符串</returns> public static string PostByHttpClient(string url, object data) { string jsonString = string.Empty; using (var client = new HttpClient(new HttpClientHandler() { AutomaticDecompression = DecompressionMethods.Deflate | DecompressionMethods.GZip })) { var jsonToSend = JsonConvert.SerializeObject(data, Formatting.None, new IsoDateTimeConverter()); var body = new StringContent(jsonToSend, Encoding.UTF8, "application/json"); var taskResponse = client.PostAsync(url, body); taskResponse.Wait(); if (taskResponse.IsCompletedSuccessfully) { var taskStream = taskResponse.Result.Content.ReadAsStreamAsync(); taskStream.Wait(); using (var reader = new StreamReader(taskStream.Result)) { jsonString = reader.ReadToEnd(); } } } return jsonString; } /// <summary> /// 通过数据来自HttpContent的HttpClient发起Post请求 /// </summary> /// <param name="url">请求地址</param> /// <param name="content">请求参数</param> /// <returns>JSON字符串</returns> public static string PostByHttpClientFromHttpContent(string url, HttpContent content) { string jsonString = string.Empty; using (var client = new HttpClient(new HttpClientHandler() { AutomaticDecompression = DecompressionMethods.Deflate | DecompressionMethods.GZip })) { var taskResponse = client.PostAsync(url, content); taskResponse.Wait(); if (taskResponse.IsCompletedSuccessfully) { var taskStream = taskResponse.Result.Content.ReadAsStreamAsync(); taskStream.Wait(); using (var reader = new StreamReader(taskStream.Result)) { jsonString = reader.ReadToEnd(); } } } return jsonString; } /// <summary> /// Object转换为StreamContent /// </summary> /// <param name="data">请求参数</param> /// <returns>StreamContent</returns> public static HttpContent ToStreamContent(this object data) { var json = JsonConvert.SerializeObject(data, Formatting.None, new IsoDateTimeConverter()); byte[] bytes = Encoding.UTF8.GetBytes(json); MemoryStream ms = new MemoryStream(); ms.Write(bytes, 0, bytes.Length); ms.Position = 0; HttpContent streamContent = new StreamContent(ms); return streamContent; } /// <summary> /// Object转换为StringContent /// </summary> /// <param name="data">请求参数</param> /// <returns>StringContent</returns> public static HttpContent ToStringContent(this object data) { HttpContent stringContent = new StringContent(JsonConvert.SerializeObject(data)); return stringContent; } /// <summary> /// Object转换为MultipartFormDataContent /// </summary> /// <param name="data"></param> /// <returns>MultipartFormDataContent</returns> public static HttpContent ToMultipartFormDataContent(this object data) { var json = JsonConvert.SerializeObject(data, Formatting.None, new IsoDateTimeConverter()); var body = new StringContent(json, Encoding.UTF8, "application/json"); var multipartFormDataContent = new MultipartFormDataContent(); multipartFormDataContent.Add(body); return multipartFormDataContent; } /// <summary> /// Object转换为FormUrlEncodedContent /// </summary> /// <param name="data">请求参数</param> /// <returns>FormUrlEncodedContent</returns> public static HttpContent ToFormUrlEncodedContent(this object data) { var param = new List<KeyValuePair<string, string>>(); var values = JObject.FromObject(data); foreach (var item in values) { param.Add(new KeyValuePair<string, string>(item.Key, item.Value.ToString())); } HttpContent formUrlEncodedContent = new FormUrlEncodedContent(param); return formUrlEncodedContent; } /// <summary> /// Object转换为ByteArrayContent /// </summary> /// <param name="data">请求参数</param> /// <returns>FormUrlEncodedContent</returns> public static HttpContent ToByteArrayContent(this object data) { var json = JsonConvert.SerializeObject(data, Formatting.None, new IsoDateTimeConverter()); byte[] bytes = Encoding.UTF8.GetBytes(json); HttpContent byteArrayContent = new ByteArrayContent(bytes); return byteArrayContent; } /// <summary> /// Url编码 /// </summary> /// <param name="content">内容</param> /// <param name="encode">编码类型</param> /// <returns></returns> private static string Encode(string content, Encoding encode = null) { if (encode == null) return content; return System.Web.HttpUtility.UrlEncode(content, Encoding.UTF8); } /// <summary> /// Url解码 /// </summary> /// <param name="content">内容</param> /// <param name="encode">编码类型</param> /// <returns></returns> private static string Decode(string content, Encoding encode = null) { if (encode == null) return content; return System.Web.HttpUtility.UrlDecode(content, Encoding.UTF8); } /// <summary> /// 将键值对参数集合拼接为Url字符串 /// </summary> /// <param name="paramArray">键值对集合</param> /// <param name="encode">转码类型</param> /// <returns></returns> private static string BuildParam(List<KeyValuePair<string, string>> paramArray, Encoding encode = null) { string url = ""; if (encode == null) encode = Encoding.UTF8; if (paramArray != null && paramArray.Count > 0) { var parms = ""; foreach (var item in paramArray) { parms += string.Format("{0}={1}&", Encode(item.Key, encode), Encode(item.Value, encode)); } if (parms != "") { parms = parms.TrimEnd('&'); } url += parms; } return url; } } }
时间仓促，没能说的太详细，有时间再做补充。如本文中的有错误示范，欢迎指正