不确定我在这里错过了什么,但我无法从我的应用程序设置中获得值。Json在我的。net核心应用程序。我有我的appsettings。json:

{
    "AppSettings": {
        "Version": "One"
    }
}

启动:

public class Startup
{
    private IConfigurationRoot _configuration;
    public Startup(IHostingEnvironment env)
    {
        _configuration = new ConfigurationBuilder()
    }
    public void ConfigureServices(IServiceCollection services)
    {
      //Here I setup to read appsettings        
      services.Configure<AppSettings>(_configuration.GetSection("AppSettings"));
    }
}

模型:

public class AppSettings
{
    public string Version{ get; set; }
}

控制器:

public class HomeController : Controller
{
    private readonly AppSettings _mySettings;

    public HomeController(IOptions<AppSettings> settings)
    {
        //This is always null
        _mySettings = settings.Value;
    }
}

_mySettings总是空的。我是不是遗漏了什么?


当前回答

花了一个小时试图解决同样的问题,我的解决方案是为appconfig添加PreserveNewest/CopyAlways。csproj中的Json

<None Update="appsettings.json">
  <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
</None>

其他回答

再加上David Liang对Core 2.0的回答——

appsettings。json文件链接到ASPNETCORE_ENVIRONMENT变量。

ASPNETCORE_ENVIRONMENT可以设置为任何值,但是框架支持三个值:Development、Staging和Production。如果没有设置ASPNETCORE_ENVIRONMENT,它将默认为Production。

对于这三个值,这些appsettings.ASPNETCORE_ENVIRONMENT。json文件支持开箱即用- appsettings.Staging。appsettings.Development.json和appsettings.Production.json

以上三个应用程序设置json文件可用于配置多个环境。

示例- appsettings.Staging.json

{
    "Logging": {
        "IncludeScopes": false,
        "LogLevel": {
            "System": "Information",
            "Microsoft": "Information"
        }
    },
    "MyConfig": "My Config Value for staging."
}

使用Configuration["config_var"]检索任何配置值。

public class Startup
{
    public Startup(IHostingEnvironment env, IConfiguration config)
    {
        Environment = env;
        Configuration = config;
        var myconfig = Configuration["MyConfig"];
    }

    public IConfiguration Configuration { get; }
    public IHostingEnvironment Environment { get; }
}
    public static void GetSection()
    {
        Configuration = new ConfigurationBuilder()
            .SetBasePath(env.ContentRootPath)
            .AddJsonFile("appsettings.json")
            .Build();

        string BConfig = Configuration.GetSection("ConnectionStrings")["BConnection"];

    }

这里是一个关于。net框架和Core: web的抽象。Config, app.config和appsettings.json

    static SafeDictionary<string, string> _appSettings;

    public static SafeDictionary<string, string> AppSettings {
        get {
            if (_appSettings == null)
            {
                _appSettings = ConfigurationManager.AppSettings
                    .ToDictionary()
                    .ToSafe();

                BuildAppSettings( JsonAppSettings, "");

            }

            return _appSettings;
        }
    }


    static SafeDictionary<string, string> _connectionStrings;

    public static SafeDictionary<string, string> ConnectionStrings
    {
        get
        {
            if (_connectionStrings == null)
            {
                _connectionStrings = ConfigurationManager.ConnectionStrings
                    .Cast<ConnectionStringSettings>()
                    .ToDictionary(x => x.Name, x => x.ConnectionString)
                    .ToSafe();

                foreach (var jp in JsonAppSettings["ConnectionStrings"].Cast<JProperty>())
                    _connectionStrings.Add(jp.Name, jp.Value.ToString() );

            }

            return _connectionStrings;
        }
    }

https://github.com/bitministry/common

亚比谢克的回答是:

如果你想将值导入到静态类中,那么只需使用(ReSharper推荐):

static IConfiguration conf = (JsonConfigurationExtensions.AddJsonFile(new ConfigurationBuilder().SetBasePath(Directory.GetCurrentDirectory()), "appsettings.json").Build());

private static string AuthorizationServiceURL { get; } = conf["ServiceUrls:AuthorizationUrl"];

// appsettings.json
{
  "ServiceUrls": {
    "AuthorizationUrl": "https://example.com/authorize"
  } 
}

. net core 3。X

不需要创建新的模型并在Startup.cs中设置。

控制器 添加新包-使用Microsoft.Extensions.Configuration;

public class HomeController : Controller
{
    private readonly IConfiguration _mySettings;

    public HomeController (IConfiguration mySettings)
    {
         _mySettings= mySettings;
    }
 
    //ex: you can get value on below function 
    public IEnumerable<string> Get()
    {
        var result = _config.GetValue<string>("AppSettings:Version"); // "One"
        return new string[] { result.ToString() };
    }
}