webapi怎麼返回json（webapi請求方式）

本文目錄一覽：

• 1、如何設置webapi返回json或jsonp
• 2、webapi 如何返回json字符串？
• 3、怎麼讓webapi返回json

如何設置webapi返回json或jsonp

ing System.Net;

using System.Net.Http.Formatting;

using System.Net.Http.Headers;

using System.Threading.Tasks;

using System.Web;

using System.Net.Http;

using Newtonsoft.Json.Converters;

using System.Web.Http;

namespace Westwind.Web.WebApi

{

/// summary

/// Handles JsonP requests when requests are fired with text/javascript

/// /summary

public class JsonpFormatter : JsonMediaTypeFormatter

{

public JsonpFormatter()

{

SupportedMediaTypes.Add(new MediaTypeHeaderValue(“application/json”));

SupportedMediaTypes.Add(new MediaTypeHeaderValue(“text/javascript”));

JsonpParameterName = “callback”;

}

/// summary

/// Name of the query string parameter to look for

/// the jsonp function name

/// /summary

public string JsonpParameterName {get; set; }

/// summary

/// Captured name of the Jsonp function that the JSON call

/// is wrapped in. Set in GetPerRequestFormatter Instance

/// /summary

private string JsonpCallbackFunction;

webapi 如何返回json字符串？

方法一：(改配置法)

找到Global.asax文件，在Application_Start()方法中添加一句：

protected void Application_Start()

{

AreaRegistration.RegisterAllAreas();

WebApiConfig.Register(GlobalConfiguration.Configuration);

FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);

RouteConfig.RegisterRoutes(RouteTable.Routes);

// 使api返回為json

GlobalConfiguration.Configuration.Formatters.XmlFormatter.SupportedMediaTypes.Clear();

}

怎麼讓webapi返回json

返回的時候封裝成json即可。

參考： Student st1 = new Student(1, “dg”, 18, new Date());

Student st2 = new Student(2, “dg”, 18, new Date());

Student st3 = new Student(3, “dg”, 18, new Date());

Student st4 = new Student(4, “dg”, 18, new Date());

Student st5 = new Student(5, “dg”, 18, new Date());

List li = new ArrayList();

JSONObject JO1 = new JSONObject(st1);

JSONObject JO2 = new JSONObject(st2);

JSONObject JO3 = new JSONObject(st3);

JSONObject JO4 = new JSONObject(st4);

JSONObject JO5 = new JSONObject(st5);

li.add(JO1);

li.add(JO2);

li.add(JO3);

li.add(JO4);

li.add(JO5);

JSONArray Ja = new JSONArray(li);

Map ma = new HashMap();

ma.put(“Result”, “OK”);

ma.put(“Records”, Ja);

JSONObject js = new JSONObject(ma);

out.print(js);

返回結果：

{“Result”:”OK”,”Records”:[{“recordDate”:”Fri Dec 16 17:54:39 CST 2011″,”name”:”dg”,”age”:18,”personId”:1},{“recordDate”:”Fri Dec 16 17:54:39 CST 2011″,”name”:”dg”,”age”:18,”personId”:2},{“recordDate”:”Fri Dec 16 17:54:39 CST 2011″,”name”:”dg”,”age”:18,”personId”:3},{“recordDate”:”Fri Dec 16 17:54:39 CST 2011″,”name”:”dg”,”age”:18,”personId”:4},{“recordDate”:”Fri Dec 16 17:54:39 CST 2011″,”name”:”dg”,”age”:18,”personId”:5}]}

可以將存放Java對象的 列表 直接轉化為 json 數組 或對象，不必要過分麻煩的轉換。

從數據庫取出後換：

SourceDao sd = new SourceDao();

JSONArray ja = new JSONArray(sd.query(content));