.NET Core 类库中读取appsettings.json

{
  "Logging": {
    "IncludeScopes": false,
    "LogLevel": {
      "Default": "Warning"
    }
  },
  "AppSettings": {
    "SqlServerConnection": "Server=127.0.0.1;Database=demo;User ID=sa;Password=sa;",
    "RedisCaching": {
      "Enabled": true,
      "ConnectionString": "127.0.0.1:6379"
    }
  }
}

1、初始化注入方式

　　Startup.cs下ConfigureServices方法：

services.AddOptions();
services.Configure<AppSettings>(Configuration.GetSection("AppSettings"));

public class AppSettings
{
      public RedisCaching RedisCaching { get; set; }
}

public class RedisCaching
{
     /// <summary>
     /// 是否启用
     /// </summary>
     public bool Enabled { get; set; }
     /// <summary>
     /// 链接信息
     /// </summary>
     public string ConnectionString { get; set; }
}

然后在控制器中调用：

public readonly IOptions<AppSettings> Setting;
public HomeController(IOptions<AppSettings> setting)
{
    Setting = setting;
}

public IActionResult Index()
{
    var s = Setting.Value.RedisCaching.ConnectionString;
    ViewData["abc"] = s;
    return View();
}

2、读取appsettings.json方式

　　 (此方法如在单独的类库中需引用Microsoft.Extensions.Options.ConfigurationExtensions、Microsoft.Extensions.Configuration.FileExtensions、Microsoft.Extensions.Configuration.Json)

　　1)先设置appsettings.json文件复制到根目录.右键appsettings.json 高级 复制到输出目录中选“始终复制”.

　　　　

　　2）

　　　　 public T Get<T>(string key)
        {
            IConfiguration config = new ConfigurationBuilder().SetBasePath(Directory.GetCurrentDirectory())
                .AddJsonFile("appsettings.json", true, true).Build();

           return config.GetSection(key).Get<T>();
        }

　　　　 public IActionResult Index()
        {
            var s = new GetAppSetting().Get<string>("AppSettings:SqlServerConnection"); 
            ViewData["abc"] = s;
            return View();
        }

第一种方法在别的类库中也可调用，比较方便，刚做core项目，用第一种方法时类库中不好调用，查了半天用第二种就可以了。