asp.net core 读取配置不同文件的两种方法

第一种是读取appsettings.json
新建的项目它默认是和源代码根目录在一起的，内容如下

{"Logging": {"LogLevel": {"Default": "Information","Microsoft.AspNetCore": "Warning"}},"AllowedHosts": "*"
}

在程序启动的Program.cs时就有如下代码

using coreapiauth;
using coreapiauth.TestWebApi.AuthCenter.Utility;
using Microsoft.AspNetCore.Authentication.JwtBearer;
using Microsoft.IdentityModel.Tokens;
using System.Text;var builder = WebApplication.CreateBuilder(args);

所以拿到builder就可以了

if (builder.Configuration["SecurityKey"]==null|| builder.Configuration["SecurityKey"].Length==0)
{throw new Exception("please defined key on appsettings.json [SecurityKey issuer audience] is must!");
}

在控制器中如何拿到呢？

这就需要定义构造方法了，之前默认构造方法是不带参数的，改成带参数的,不过看上去不是复写方法，和java语法不同，这种注入不需要定义什么注解它就能给你传递进来。

using Microsoft.AspNetCore.Authentication;using Microsoft.AspNetCore.Authorization;using Microsoft.AspNetCore.Mvc;using Microsoft.Extensions.Configuration;using Microsoft.Extensions.Logging;using Newtonsoft.Json;//using TestWebApi.AuthCenter.Utility;namespace TestWebApi.AuthCenter.Controllers{[Route("api/[controller]")][ApiController]public class AuthController : ControllerBase{//需要注入的服务private readonly ILogger<AuthController> _logger;private readonly IConfiguration _configuration;private readonly IJwtService _jwtService;public AuthController(IConfiguration configuration,ILogger<AuthController> logger,IJwtService jwtService){_configuration = configuration;_logger = logger;_jwtService = jwtService;}}}

或者
···

private readonly IConfiguration _iConfiguration = null;
public ConfigurationController(IConfiguration configuration)
{
this._iConfiguration = configuration;

}

···
第二种
这种会生成一个你的程序名(.dll|.exe).config这种似乎不方便调试在源代码阶段，这个配置文件和源代码并不是在一起的，而且它默认是没有的。

using System.Configuration;
using System.Data.SqlClient;
using webapi_test.consts;
using ConfigurationManager = System.Configuration.ConfigurationManager;namespace webapi_test.utils
{public class ConfigUtil{public static void init(){Configuration cfa = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);if (cfa.AppSettings.Settings["LaunchTime"] == null){cfa.AppSettings.Settings.Add("LaunchTime", "");cfa.AppSettings.Settings.Add("DataSource", "");cfa.AppSettings.Settings.Add("InitialCatalog", "");cfa.AppSettings.Settings.Add("Password", "");cfa.AppSettings.Settings.Add("UserID", "SA");cfa.AppSettings.Settings.Add("ConnectTimeout", "15");}else{String DataSource = cfa.AppSettings.Settings["DataSource"]?.Value??"";if (DataSource != null&&DataSource.Length>0){String InitialCatalog = cfa.AppSettings.Settings["InitialCatalog"]?.Value??"";String UserID = cfa.AppSettings.Settings["UserID"]?.Value??"";int ConnectTimeout =ParseUtil.parseInt(cfa.AppSettings.Settings["ConnectTimeout"]?.Value ?? "15");String Password = cfa.AppSettings.Settings["Password"]?.Value ?? "";Consts.strConn= SercretCS. Conn = new SqlConnectionStringBuilder(){DataSource = DataSource,InitialCatalog = InitialCatalog,//UserID = UserID,ConnectTimeout = ConnectTimeout,Password = Password}.ConnectionString;}}cfa.AppSettings.Settings["launchTime"].Value = DateTime.Now.ToString();cfa.Save();}}
}

如果写入成功内容如下:

<?xml version="1.0" encoding="utf-8"?>
<configuration><appSettings><add key="LaunchTime" value="xxx" /><add key="DataSource" value="xxx" /><add key="InitialCatalog" value="xxx" /><add key="Password" value="xxx" /><add key="UserID" value="SA" /><add key="ConnectTimeout" value="15" /></appSettings>
</configuration>