.net6 使用 JWT

1. 安装 Nuget 包 Microsoft.AspNetCore.Authentication.JwtBearer

2. Program.cs 里添加JWT

   //添加jwt验证：
   builder.Services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme).AddJwtBearer(options=>
   {
       options.TokenValidationParameters = new TokenValidationParameters()
       {
           ValidateIssuer = true,
           ValidIssuer = builder.Configuration["JWT:Issuer"],
           ValidateAudience = true,
           ValidAudience = builder.Configuration["JWT:Audience"],
           ValidateLifetime = true,
           IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(builder.Configuration["JWT:SecretKey"]))
       };
   });
   

3. 下面的app添加这个

   app.UseAuthentication();

   app.UseAuthorization();

   app.UseHttpsRedirection();
   
   app.UseCors();
   
   app.UseAuthentication();//在前 鉴权
   app.UseAuthorization();//在后  授权
   
   app.MapControllers();
   
   app.Run();
   

4. TokenHelper类 模型也放在这里 比如我放了一个实体进去拿token的时候也会拿出一个实体

   public class TokenHelper
   {
   	private readonly IConfiguration _configuration;
   	private readonly JwtSecurityTokenHandler _jwtSecurityTokenHandler;
   	public TokenHelper(IConfiguration configuration, JwtSecurityTokenHandler jwtSecurityTokenHandler)
   	{
   	    _configuration = configuration;
   	    _jwtSecurityTokenHandler = jwtSecurityTokenHandler;
   	}
   	/// <summary>
   	/// 创建加密JwtToken
   	/// </summary>
   	/// <param name="user"></param>
   	/// <returns></returns>
   	public string CreateJwtToken<T>(T user)
   	{
   	  var claimList = this.CreateClaimList(user);
   	  //  从 appsettings.json 中读取SecretKey
   	  var secretKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(_configuration["JWT:SecretKey"]));
         // 从 appsettings.json 中读取Expires
         var expires = Convert.ToDouble(_configuration["JWT:Expires"]);
         //  选择加密算法
         var algorithm = SecurityAlgorithms.HmacSha256;
         // 生成Credentials
         var signingCredentials = new SigningCredentials(secretKey, algorithm);
         JwtSecurityToken jwtSecurityToken = new JwtSecurityToken(
            _configuration["JWT:Issuer"],     //Issuer
             _configuration["JWT:Audience"],   //Audience
             claims: claimList,
             DateTime.Now,                    //notBefore
             DateTime.Now.AddDays(expires),   //expires
             signingCredentials               //Credentials
             );
          string jwtToken = _jwtSecurityTokenHandler.WriteToken(jwtSecurityToken);
          return jwtToken;
        }
   
        public T GetToken<T>(string Token)
        {
          Type t = typeof(T
          object objA = Activator.CreateInstance(t);
          var b = _jwtSecurityTokenHandler.ReadJwtToken(Token);
          foreach (var item in b.Claims)
          {
             PropertyInfo _Property = t.GetProperty(item.Type);
             if (_Property != null && _Property.CanRead)
             {
                 _Property.SetValue(objA, item.Value, null);
             }
          }
          return (T)objA;
        }
   
        /// <summary>
        /// 创建包含用户信息的CalimList
        /// </summary>
        /// <param name="authUser"></param>
        /// <returns></returns>
        private List<Claim> CreateClaimList<T>(T authUser)
        {
           var Class = typeof(T);
           List<Claim> claimList = new List<Claim>();
           foreach (var item in Class.GetProperties())
           {
               claimList.Add(new Claim(item.Name, Convert.ToString(item.GetValue(authUser))));
           }
           return claimList;
        }
   }
   

5. appsettings.json

    "JWT": {
       "Issuer": "随意默认是自己的域名",//发行人
       "Audience": "前端随写",//拥有者
       "SecretKey": "666666666666666666",//16位以上
       "Expires": 7//过期时间 单位：天
     }
   

6. 控制器中颁发token

   [Authorize]//授权
   //控制器
   private readonly TokenHelper _tokenHelper;
   private readonly IUserService _userServices;
   public UserController(IUserService userServices,TokenHelper tokenHelper)
   {
       _userServices = userServices;
       _tokenHelper = tokenHelper;
   }
   /// <summary>
   /// 登录
   /// </summary>
   /// <param name="user"></param>
   /// <returns></returns>
   [AllowAnonymous]
   [HttpPost]
   public IActionResult Login(LoginDto user)
   {
       if (user==null)
       {
           return BadRequest();
       }
       var result = _userServices.Login(user);
       if (result==null)
       {
           return Ok(new ResponseModel { Code = 0, Message = "登录失败" });
       }
       //颁发token
       var token = _tokenHelper.CreateJwtToken(result);
       Response.Headers["Header_Token"] = token;
       Response.Headers["Access-Control-Expose-Headers"] = "token";
       return Ok(new ResponseModel { Code=1, Data=result, Message="登录成功" });
   }