相关配置
<Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>netcoreapp3.1</TargetFramework>
</PropertyGroup>
<ItemGroup>
<!--读取配置的核心包-->
<PackageReference Include="Microsoft.Extensions.Configuration" Version="3.1.0" />
<!--Json中提取配置-->
<PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="3.1.0" />
<!--Xml中提取配置-->
<PackageReference Include="Microsoft.Extensions.Configuration.Xml" Version="3.1.0" />
<!--Ini中提取配置-->
<PackageReference Include="Microsoft.Extensions.Configuration.Ini" Version="3.1.0" />
<!--环境变量中提取配置-->
<PackageReference Include="Microsoft.Extensions.Configuration.EnvironmentVariables" Version="3.1.0" />
<!--命令行中提取配置-->
<PackageReference Include="Microsoft.Extensions.Configuration.CommandLine" Version="3.1.0" />
<!--依赖注入-->
<PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="3.1.0" />
<!--将配置数据绑定到对象的相关引用-->
<PackageReference Include="Microsoft.Extensions.Options" Version="3.1.0" />
<PackageReference Include="Microsoft.Extensions.Configuration.Binder" Version="3.1.0" />
</ItemGroup>
<ItemGroup>
<None Update="tsconfig.ini">
<CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
</None>
<None Update="tsconfig.json">
<CopyToOutputDirectory>Always</CopyToOutputDirectory>
</None>
<None Update="tsconfig.xml">
<CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
</None>
</ItemGroup>
</Project>
//tsconfig.dev.json
{
"ConnectionStrings": {
"db1": "dev_xx1,xx",
"db2": "dev_xx2,xx"
},
"t1": {
"t2": {
"t3": "dev_t1_t2_t3_val"
}
},
"c1": {
"c2": "dev_c1_c2_val"
},
"d1": {
"d2": "dev_d1_d2_val"
}
}
//tsconfig.json
{
"ConnectionStrings": {
"db1": "xx1,xx",
"db2": "xx2,xx"
},
"t1": {
"t2": {
"t3": "t1_t2_t3_val"
}
},
"c1": {
"c2": "c1_c2_val"
},
"d1": {
"d2": "d1_d2_val"
}
}
//tsconfig.ini
MyKey="MyIniConfig.ini Value"
[Position]
Title="My INI Config title"
Name="My INI Config name"
[Logging:LogLevel]
Default=Information
Microsoft=Warning
//tsconfig.xml
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<MyKey>MyXMLFile Value</MyKey>
<Position>
<Title>Title from MyXMLFile</Title>
<Name>Name from MyXMLFile</Name>
</Position>
<Logging>
<LogLevel>
<Default>Information</Default>
<Microsoft>Warning</Microsoft>
</LogLevel>
</Logging>
</configuration>
读取环境变量
引用:
<PackageReference Include="Microsoft.Extensions.Configuration.EnvironmentVariables" Version="3.1.0" />
ConfigurationBuilder configBuilder = new ConfigurationBuilder();
configBuilder.AddEnvironmentVariables(prefix: "test_");
var config = configBuilder.Build();
//读取test_p1环境变量的值,这里不需要【test_】前缀
var p1 = config["p1"];
Console.WriteLine($"test_1:{p1}");
运行结果 :
示例代码说明:
1、test_ 前缀的环境变量会被加载到程序,如果没有前缀会加载所有环境变量。
2、需要注意的是,在读取环境变量时不需要前缀。
3、DOTNET_ 和 ASPNETCORE_ 前缀会由 ASP.NET Core 用于主机和应用配置,但不用于用户配置,详细介绍可以参考:https://learn.microsoft.com/zh-cn/aspnet/core/fundamentals/host/generic-host?view=aspnetcore-7.0
读取配置文件
注意:需要设置tsconfig.json文件的属性为【如果较新则复制】或【者始终复制】
ConfigurationBuilder configBuilder = new ConfigurationBuilder();
/*
optional:参数表示这个文件是否可选,如果它的值为true,则当配置文件不存在的时候,程序不会报错;如果它的值为false,当配置文件不存在的时候,程序会报错
eloadOnChange:参数表示如果文件修改了,是否重新加载配置
*/
configBuilder.AddJsonFile("tsconfig.json", optional: false, reloadOnChange: false);
IConfigurationRoot config = configBuilder.Build();
//获取连接字符串,读取“ConnectionStrings”节点下的名为【db2】的连接字符串值
var conn = config.GetConnectionString("db2");
Console.WriteLine($"conn:{conn}");
string value = config.GetSection("t1:t2:t3").Value;
Console.WriteLine($"value={value}");
运行结果:
读取Ini配置
ConfigurationBuilder configBuilder = new ConfigurationBuilder();
configBuilder.AddEnvironmentVariables(prefix: "test_");
configBuilder.AddIniFile("tsconfig.ini", optional: false, reloadOnChange: false);
IConfigurationRoot config = configBuilder.Build();
var myKeyValue = config["MyKey"];
var title = config["Position:Title"];
var positionName = config["Position:Name"];
var defaultLogLevel = config["Logging:LogLevel:Default"];
Console.WriteLine($"MyKey value: {myKeyValue} \n" +
$"Title: {title} \n" +
$"Name: {positionName} \n" +
$"Default Log Level: {defaultLogLevel}");
运行结果:
读取Xml配置
ConfigurationBuilder configBuilder = new ConfigurationBuilder();
configBuilder.AddEnvironmentVariables(prefix: "test_");
configBuilder.AddXmlFile("tsconfig.xml", optional: false, reloadOnChange: false);
IConfigurationRoot config = configBuilder.Build();
var myKeyValue = config["MyKey"];
var title = config["Position:Title"];
var positionName = config["Position:Name"];
var defaultLogLevel = config["Logging:LogLevel:Default"];
Console.WriteLine($"MyKey value: {myKeyValue} \n" +
$"Title: {title} \n" +
$"Name: {positionName} \n" +
$"Default Log Level: {defaultLogLevel}");
运行结果:
使用选项方式读取配置
//注意:reloadOnChange 需要设置为true
ConfigurationBuilder configBuilder = new ConfigurationBuilder();
configBuilder.AddJsonFile("tsconfig.json", optional: false, reloadOnChange: true);
IConfigurationRoot config = configBuilder.Build();
//配置依赖注入
IServiceCollection services = new ServiceCollection();
services.AddOptions().Configure<OptionConnectionStrings>(c => config.GetSection("ConnectionStrings").Bind(c));
services.AddTransient<Demo>();
using (var sp = services.BuildServiceProvider())
{
while (true)
{
using (var scope = sp.CreateScope())
{
var spScope = scope.ServiceProvider;
var demo = spScope.GetRequiredService<Demo>();
demo.Test();
}
Console.WriteLine("可以改配置啦");
Console.ReadKey();
}
}
public class Demo
{
/*
1、IOptions<T>在配置改变后,我们不能读到新的值,必须重启程序才可以读到新的值;
2、IOptionsMonitor<T>在配置改变后,我们能读到新的值;
3、IOptionsSnapshot<T>也是在配置改变后,我们能读到新的值,和IOptionsMonitor<T>不同的是,在同一个范围内IOptionsMonitor<T>会保持一致性。
通俗地说,在一个范围内,如果有A、B两处代码都读取了某个配置项,在运行A之后且在运行B之前,这个配置项改变了,那么如果我们用IOptionsMonitor<T>读取配置,
在A处读到的将会是旧值,而在B处读到的是新值;如果我们用IOptionsSnapshot<T>读取配置,在A处和B处读到的都是旧值,只有再次进入这个范围才会读到新值
*/
//private readonly IOptions<OptionConnectionStrings> optDbSettings;
//private readonly IOptionsMonitor<OptionConnectionStrings> optDbSettings;
private readonly IOptionsSnapshot<OptionConnectionStrings> optDbSettings;
public Demo(IOptionsSnapshot<OptionConnectionStrings> optDbSettings)
{
this.optDbSettings = optDbSettings;
}
public void Test()
{
var db = optDbSettings.Value;
Console.WriteLine($"数据库:{db.db1},{db.db2}");
}
}
第一次运行和修改配置文件后运行结果:
命令行读取配置
ConfigurationBuilder configBuilder = new ConfigurationBuilder();
configBuilder.AddCommandLine(args);
IConfigurationRoot config = configBuilder.Build();
/*
这里所用“:”号分层,对应json 格式为:
{
"t1":{
"t2":{
"t3":"t1_t2_t3_val"
}
}
}
*/
string server = config["t1:t2:t3"];
Console.WriteLine($"value:{server}");
运行结果:
多源配置读取顺序分析
配置顺序如下:
1、配置文件
2、环境变量
3、命令行
结论:后添加的配置提供程序中的配置覆盖会之前的配置
ConfigurationBuilder configBuilder = new ConfigurationBuilder();
configBuilder
.AddJsonFile("tsconfig.json", optional: false, reloadOnChange: true)
.AddJsonFile("tsconfig.dev.json", optional: false, reloadOnChange: true)
.AddEnvironmentVariables()
.AddCommandLine(args);
IConfigurationRoot config = configBuilder.Build();
Console.WriteLine($"t1:t2:t3={config["t1:t2:t3"]}\r\n" +
$"c1:c2={config["c1:c2"]}\r\n" +
$"d1:d2={config["d1:d2"]}\r\n" +
$"ConnectionStrings:db1={config["ConnectionStrings:db1"]}");
运行结果:
红色字体代表最终的输出结果:
添加顺序 | ConnectionStrings:db1 | t1:t2:t3 | c1:c2 | d1:d2 |
dev.json配置文件 | dev_xx1,xx | dev_t1_t2_t3_val | dev_c1_c2_val | dev_d1_d2_val |
json配置文件 | xx1,xx | t1_t2_t3_val | c1_c2_val | d1_d2_val |
环境变量 | s_c1_c2_val | s_d1_d2_val | ||
命令行 | m_t1_t2_t3_val | m_d1_d2_val |
参考:
【.NET Core框架】配置(Configuration) - .Neterr - 博客园
ASP.NET Core 中的配置 | Microsoft Learn