配置文件，是一个每个应用服务程序常用的功能，从原来的终端应用时代，到现在的元宇宙时代，配置都是很悠然自得的存在。asp.net core提供了强大的配置文件访问机制，不管是MVC API还是MiniAPI，使用方式都是相同的。

框架默认的配置文件是：appsettings.json，可以以json的格式存放自己复杂的配置:

{"Logging": {"LogLevel": {"Default": "Information","Microsoft.AspNetCore": "Warning"}},"AllowedHosts": "*","ConnectionStrings": {"ExamDatabase": "server=.;database=Exam;uid=sa;pwd=sa;"},"AppInfo": {"Name": "Mini & Powerful","Version": "v1.0.0","Author": {"Architect": "桂素伟-A","Programmer": "桂素伟-P","Designer": "桂素伟-D"},"Features": [ "Learn MiniAPI", "Architect Element" ]}
}

简单取值

var architect = builder.Configuration.GetSection("AppInfo:Author:Architect").Value;
var features1=builder.Configuration.GetSection("AppInfo:Features:1").Value;

用record绑定

record

public record AppInfoRecord(string? Name, string? Version, AuthorRecord? Author, string[]? Features);
public record AuthorRecord(string? Architect, string? Programmer, string? Designer);

绑定

var authorRecord = new AuthorRecord(null, null, null);
var appInfoRecord = new AppInfoRecord(null, null, authorRecord, null);
builder.Configuration.GetSection("AppInfo").Bind(appInfoRecord);

结果

用class绑定

class

public class AppInfo
{public string? Name { get; set; }public string? Version { get; set; }public Author? Author { get; set; }public string[]? Features { get; set; }
}
public class Author
{public string? Architect { get; set; }public string? Programmer { get; set; }public string? Designer { get; set; }
}

绑定

var appInfo = new AppInfo();
builder.Configuration.GetSection("AppInfo").Bind(appInfo);

结果

用record和class绑定各有优势，record定义的时间代码简单，绑定要复杂一些，class正好相反，定义要复杂一些，绑定时简单。

从IConfiguration中获取配置

可以在路由方法中获取配置信息

app.MapGet("/getappinfo", (IConfiguration config) =>
{return config.GetSection("AppInfo:Name").Value;
});

从路由中取配置文件

首选注入

var authorRecord = new AuthorRecord(null, null, null);
var appInfoRecord = new AppInfoRecord(null, null, authorRecord, null);
builder.Configuration.GetSection("AppInfo").Bind(appInfoRecord);
builder.Services.AddSingleton(appInfoRecord);

取配置数据

app.MapGet("/appinfo", (AppInfoRecord appinfo) =>
{return appinfo;
});

结果

读取其他格式的配置文件

myconfig.ini

[iniconfig]
key1=value1
key2=value2

加载配置文件，并取值

builder.Host.ConfigureAppConfiguration((hostingContext, config) =>
{config.AddIniFile("myconfig.ini",optional: true,reloadOnChange: true);
});var key1=builder.Configuration.GetSection("iniconfig:key1").Value;