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?
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"
}
}
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; }
}
ASP。NET Core 3.1你可以遵循以下指南:
https://learn.microsoft.com/en-us/aspnet/core/fundamentals/configuration/?view=aspnetcore-3.1
当您创建一个新的ASP。在Program.cs中，你会有如下的配置行:
Host.CreateDefaultBuilder(args)
这将启用以下功能:
ChainedConfigurationProvider : Adds an existing IConfiguration as a
source. In the default configuration case, adds the host
configuration and setting it as the first source for the app
configuration.
appsettings.json using the JSON configuration
provider.
appsettings.Environment.json using the JSON configuration
provider. For example, appsettings.Production.json and
appsettings.Development.json.
App secrets when the app runs in the
Development environment.
Environment variables using the Environment
Variables configuration provider.
Command-line arguments using the
Command-line configuration provider.
这意味着您可以注入IConfiguration并使用字符串键获取值，甚至是嵌套值。像IConfiguration“父母:孩子”;
例子:
appsettings.json
{
"ApplicationInsights":
{
"Instrumentationkey":"putrealikeyhere"
}
}
WeatherForecast.cs
[ApiController]
[Route("[controller]")]
public class WeatherForecastController : ControllerBase
{
private static readonly string[] Summaries = new[]
{
"Freezing", "Bracing", "Chilly", "Cool", "Mild", "Warm", "Balmy", "Hot", "Sweltering", "Scorching"
};
private readonly ILogger<WeatherForecastController> _logger;
private readonly IConfiguration _configuration;
public WeatherForecastController(ILogger<WeatherForecastController> logger, IConfiguration configuration)
{
_logger = logger;
_configuration = configuration;
}
[HttpGet]
public IEnumerable<WeatherForecast> Get()
{
var key = _configuration["ApplicationInsights:InstrumentationKey"];
var rng = new Random();
return Enumerable.Range(1, 5).Select(index => new WeatherForecast
{
Date = DateTime.Now.AddDays(index),
TemperatureC = rng.Next(-20, 55),
Summary = Summaries[rng.Next(Summaries.Length)]
})
.ToArray();
}
}
我在WPF中遇到了类似的问题。NET Framework 5.0)
我所要做的就是登记。
services.AddSingleton<IConfiguration>(_configuration);
配置本身是这样配置的(在App.xaml.cs中):
var builder = new ConfigurationBuilder()
.SetBasePath(Directory.GetCurrentDirectory())
.AddJsonFile("appsettings.json", optional: false, reloadOnChange: true);
_configuration = builder.Build();
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"
}
}
