ASP.NET 核心 2 : Model bound complex types must not be abstract or value types and must have a parameterless constructor

Question

我想使用 IOptions 通过 POCO 获取配置，但它会抛出错误消息“模型绑定(bind)的复杂类型不能是抽象类型或值类型，并且必须具有无参数构造函数”

DatabaseSettings.cs

public class DatabaseSettings
    {
        public string MongoDBServer { get; set; }
    }

appsettings.json

"DatabaseSettings": {
    "MongoDBServer": "localhost"
  },
  "Logging": {
    "IncludeScopes": false,
    "LogLevel": {
      "Default": "Warning"
    }
  }

Startup.cs

public void ConfigureServices(IServiceCollection services)
{
      services.AddMvc();
      services.Configure<DatabaseSettings>(Configuration.GetSection("DatabaseSettings"));
}

Controller

public IActionResult Create(IOptions<DatabaseSettings> options)
{
  string test = options.Value.MongoDBServer;
  return View();
}

我不知道怎么办。你有什么建议给我吗？谢谢!

Answer 1

我遇到了同样的问题。我找到了 this回答很有帮助。

请尝试将 [FromServices] 添加到 Controller 操作:

public IActionResult Create([FromServices] IOptions<DatabaseSettings> options)