Question

我有一个ASP.NET Core WebAPI项目，我正在尝试将配置添加到我通过DI注入的IEmailService中：

services.AddTransient<IEmailSender, AuthMessageSender>();

AuthMessageSender的实例如何在配置文件中进行设置？

Answer 1

您应该使用强类型配置的options模式：

创建EmailSettings强类型配置类：

public class EmailSettings  
{
    public string HostName { get; set; }
    public string Username { get; set; }
    public string Password { get; set; }
}

更新 appsettings.json 以包含映射到EmailSettings配置类的配置部分：

{
  "Logging": {
    "IncludeScopes": false,
    "LogLevel": {
      "Default": "Debug",
      "System": "Information",
      "Microsoft": "Information"
    }
  },
  "EmailSettings": {
    "HostName": "myhost.com",
    "Username": "me",
    "Password": "mysupersecretpassword",
  }
}

在ConfigureServices类的Startup调用中，将 appsettings.json 绑定到您的配置类

public void ConfigureServices(IServiceCollection services)  
{
    services.Configure<MySettings>(
          options => Configuration.GetSection("EmailSettings").Bind(options));
}

在AuthMessageSender类中，将IOptions<EmailSettings>的实例注入构造函数

public class AuthMessageSender
{
    private readonly EmailSettings _settings;
    public AuthMessageSender(IOptions<EmailSettings> emailSettings)
    {
       _settings = emailSettings.Value;
      // _settings.HostName == "myhost.com";
    }
}

请注意，在步骤3中，您还可以使用

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

如果您在 project.json 中添加对 Microsoft.Extensions.Options.ConfigurationExtensions 的引用：

{
  "dependencies": {
     "Microsoft.Extensions.Options.ConfigurationExtensions": "1.0.0"
  }
}

Answer 2

推荐的模式是读取您需要的特定配置条目at startup并将它们存储在DI中的选项实例中，并注入特定选项类型into your other components。

ASP.NET Core Expose配置到DI注入服务

2 个答案: