首先需要在你的项目中引入JWT，你只需要在nuget中安装JWT，JWT依赖于.NET Framwork 4.6以上版本，所以你的webapi项目也需要.NET Framwork4.6以上版本，我这里做法如下：
1 /// <summary> 2 /// 验证是否含有token 3 /// </summary> 4 public class ApiAuthorizeAttribute : AuthorizeAttribute 5 { 6 private UserIBLL userBll = new UserBLL(); 7 /// <summary> 8 /// 验证是否授权 9 /// </summary> 10 /// <param name="actionContext"></param> 11 /// <returns></returns> 12 protected override bool IsAuthorized(HttpActionContext actionContext) 13 { 14 //获取header头信息 15 IEnumerable<string> tokenInfo; 16 actionContext.Request.Headers.TryGetValues("Token", out tokenInfo); 17 IEnumerable<string> id; 18 actionContext.Request.Headers.TryGetValues("id", out id); 19 if (tokenInfo != null) 20 { 21 string token = tokenInfo.ToList<string>()[0]; 22 var userid = id.ToList<string>()[0]; 23 if (!string.IsNullOrEmpty(token)) 24 { 25 try 26 { 27 UserEntity userEntity = userBll.GetEntityByUserId(id.ToList<string>()[0]); 28 if (userEntity == null) 29 { 30 return false; 31 } 32 IJsonSerializer serializer = new JsonNetSerializer(); 33 IDateTimeProvider provider = new UtcDateTimeProvider(); 34 IJwtValidator validator = new JwtValidator(serializer, provider); 35 IBase64UrlEncoder urlEncoder = new JwtBase64UrlEncoder(); 36 IJwtDecoder decoder = new JwtDecoder(serializer, validator, urlEncoder); 37 var json = decoder.Decode(token, userEntity.Secret, verify: true); 38 if (string.IsNullOrEmpty(json)) 39 { 40 return false; 41 } 42 var newModel = json.ToObject<UserEntity>(); 43 if (newModel.F_UserId != userEntity.F_UserId || newModel.Secret != userEntity.Secret) 44 { 45 return false; 46 } 47 return true; 48 } 49 catch (Exception) 50 { 51 return false; 52 } 53 } 54 } 55 return false; 56 } 57 }