.net Blazor webassembly 和 webAPI 内建支持依赖注入, Winform 和 Console 应用虽然不带有依赖注入功能, 但增加依赖注入也很简单.
本文将示例如何为 WinForm 程序增加依赖注入特性, 实现通过DI容器获取Cofiguration 实例, 并读取appsettings.json文件.
安装依赖库, 有点多
- Microsoft.Extensions.DependencyInjection 库, 依赖注入的类库
- Microsoft.Extensions.Configuration 库, 包含IConfiguration接口 和 Configuration类
- Microsoft.Extensions.Configuration.Json 库, 为 IConfiguration 增加了读取 Json 文件功能,
- Microsoft.Extensions.Hosting 库, 提供 Host 静态类, 有能力从 appsettings.{env.EnvironmentName}.json 加载相应 env 的设定值, 并将设定值用于IConfiguration/ILoggerFactory中, 同时增加 Console/EventSourceLogger 等 logger.
仅适用于 Asp.Net core 和 Console 类应用 - Microsoft.Extensions.Logging 库, 包含 ILogger 和 ILoggerFactory 接口
- Serilog.Extensions.Logging 库, 为DI 容器提供 AddSerilog() 方法.
- Serilog.Sinks.File 库, 提供 Serilog rolling logger
- Serilog.Sinks.Console 库, 增加 serilog console logger
- Serilog.Settings.Configuration 库, 允许在 appsetting.json 配置 Serilog, 顶层节点要求是 Serilog.
- Serilog.Enrichers.Thread 和 Serilog.Enrichers.Environment 库, 为输出日志文本增加 Thread和 env 信息
补充库:
- Microsoft.Extensions.Options.ConfigurationExtensions 库, 为DI容器增加了从配置文件中实例化对象的能力, 即 serviceCollection.Configure<TOptions>(IConfiguration)
- Microsoft.Extensions.Options 库, 提供以强类型的方式读取configuration文件, 这是.Net中首选的读取configuration文件方式.
appsettings.json 配置文件
配置一个 ConnectionString, 另外配 serilog
{
"ConnectionStrings": {
"oeeDb": "Server=localhost\\SQLEXPRESS01;Database=Oee;Trusted_Connection=True;"
},
"Serilog": {
"Using": [ "Serilog.Sinks.Console", "Serilog.Sinks.File" ],
"MinimumLevel": "Debug",
"WriteTo": [
{ "Name": "Console" },
{
"Name": "File",
"Args": { "path": "Logs/serilog.txt" }
}
],
"Enrich": [ "FromLogContext", "WithMachineName", "WithThreadId" ]
}
}Program.cs , 增加DI容器
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Serilog;
namespace Collector
{
internal static class Program
{
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main()
{
ApplicationConfiguration.Initialize();
//未使用依赖注入的写法
//Application.Run(new FormMain());
//生成 DI 容器
ServiceCollection services = new ServiceCollection();
ConfigureServices(services); //注册各种服务类
//先用DI容器生成 serviceProvider, 然后通过 serviceProvider 获取Main Form的注册实例
var serviceProvider =services.BuildServiceProvider();
var formMain = serviceProvider.GetRequiredService<FormMain>(); //主动从容器中获取FormMain实例, 这是简洁写法
// var formMain = (FormMain)serviceProvider.GetService(typeof(FormMain)); //更繁琐的写法
Application.Run(formMain);
}
/// <summary>
/// 在DI容器中注册所有的服务类型
/// </summary>
/// <param name="services"></param>
private static void ConfigureServices(ServiceCollection services)
{
//注册 FormMain 类
services.AddScoped<FormMain>();
//register configuration
IConfigurationBuilder cfgBuilder = new ConfigurationBuilder()
.SetBasePath(Directory.GetCurrentDirectory())
.AddJsonFile("appsettings.json")
.AddJsonFile($"appsettings.{Environment.GetEnvironmentVariable("DOTNET_ENVIRONMENT")}.json", optional: true, reloadOnChange: false)
;
IConfiguration configuration=cfgBuilder.Build();
services.AddSingleton<IConfiguration>(configuration);
//Create logger instance
var serilogLogger = new LoggerConfiguration()
.ReadFrom.Configuration(configuration)
.Enrich.FromLogContext()
.CreateLogger();
//register logger
services.AddLogging(builder => {
object p = builder.AddSerilog(logger: serilogLogger, dispose: true);
});
}
}
}FormMain.cs , 验证依赖注入的效果
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Logging;
namespace Collector
{
public partial class FormMain : Form
{
private readonly IConfiguration _configuration;
private readonly ILogger _logger;
/// <summary>
/// 为 FormMain 构造子增加两个形参, 构造子参数将由于DI容器自动注入
/// </summary>
/// <param name="configuration"></param>
/// <param name="logger">形参必须是 ILogger泛型类型, 不能是 ILogger 类型</param>
public FormMain(IConfiguration configuration, ILogger<FormMain> logger)
{
_configuration = configuration;
_logger = logger;
InitializeComponent();
var connectionString = _configuration.GetConnectionString("oeeDb"); //从配置文件中读取oeeDb connectionString
_logger.LogInformation(connectionString); //将connection String 写入到日志文件中
}
}
}DI容器管理配置文件Section
上面示例, 我们通过 _configuration.GetConnectionString("oeeDb") 可以拿到connectionString, 非常方便, 这主要是得益于.Net 已经类库已经考虑到在配置文件中存储 connectionString 是一个普遍的做法, 所以类库内置支持了.
如果在 appsettings.json 中存一些自定义的信息, 如何方便读取呢? 微软推荐的 Options 模式, 下面详细介绍.
首先安装库:
- Microsoft.Extensions.Options.ConfigurationExtensions 库, 为DI容器增加了从配置文件中实例化对象的能力, 即 serviceCollection.Configure<TOptions>(IConfiguration)
- Microsoft.Extensions.Options 库, 提供以强类型的方式读取configuration文件, 这是.Net中首选的读取configuration文件方式.
假设 appsettings.json 中要存放appKey和appSecret信息, 具体配置如下:
"AppServiceOptions": {
"appKey": "appkey1",
"appSecret": "appSecret1"
}定义对应的 Poco Class, 推荐后缀为 Options,
public class AppServiceOptions
{
public string AppKey { get; set; } = "";
public string AppSecret { get; set; } = "";
}注册函数 ConfigureServices()中, 注册 AppServiceOptions 类, 告知DI容器, 要基于配置文件AppServiceOptions section来实例化
private static void ConfigureServices(ServiceCollection services)
{
//注册 FormMain 类
services.AddScoped<FormMain>();
//register configuration
IConfigurationBuilder cfgBuilder = new ConfigurationBuilder()
.SetBasePath(Directory.GetCurrentDirectory())
.AddJsonFile("appsettings.json")
.AddJsonFile($"appsettings.{Environment.GetEnvironmentVariable("DOTNET_ENVIRONMENT")}.json", optional: true, reloadOnChange: false)
;
IConfiguration configuration=cfgBuilder.Build();
services.AddSingleton<IConfiguration>(configuration);
//Create logger instance
var serilogLogger = new LoggerConfiguration()
.ReadFrom.Configuration(configuration)
.Enrich.FromLogContext()
.CreateLogger();
//register logger
services.AddLogging(builder => {
object p = builder.AddSerilog(logger: serilogLogger, dispose: true);
});
//注册 AppServiceOptions 类, 告知DI容器, 要基于配置文件AppServiceOptions section来实例化
services.AddOptions();
services.Configure<AppServiceOptions>(configuration.GetSection("AppServiceOptions"));
}主动从DI容器中获取 AppServiceOptions 配置信息代码如下, 注意GetRequiredService函数的的泛型参数要使用 IOptions<> 包一下.
var appServiceOptionsWrapper=serviceProvider.GetRequiredService<IOptions<AppServiceOptions>>();
AppServiceOptions appServiceOptions= appServiceOptionsWrapper.Value;将 AppServiceOptions 注入到 FormMain 的代码, 和主动从DI容器中获取 AppServiceOptions 实例一样, 都需要使用 IOptions<> 接口包一下构造子形参.
public partial class FormMain : Form
{
private readonly IConfiguration _configuration;
private readonly ILogger _logger;
private AppServiceOptions _appServiceOptions;
/// <summary>
/// 为 FormMain 构造子增加三个形参, 构造子参数将由于DI容器自动注入
/// </summary>
/// <param name="configuration">形参必须是接口 IConfigurations</param>
/// <param name="logger">形参必须是 ILogger泛型类型, 不能是 ILogger 类型</param>
/// <param name="appServiceOptionsWrapper">形参必须是 IOptions 泛型接口 </param>
public FormMain(IConfiguration configuration, ILogger<FormMain> logger, IOptions<AppServiceOptions> appServiceOptionsWrapper)
{
_configuration = configuration;
_logger = logger;
_appServiceOptions = appServiceOptionsWrapper.Value;
InitializeComponent();
var connectionString = _configuration.GetConnectionString("oeeDb"); //从配置文件中读取oeeDb connectionString
_logger.LogInformation(connectionString); //将connection String 写入到日志文件中
}
private void button1_Click(object sender, EventArgs e)
{
this.Text = _appServiceOptions.AppKey;
}
}.net core 复杂 configuration Section 的读取
appsettings文件定义一个复杂的设置项, 顶层是一个json 数组, 里面又嵌套了另一个数组
"PlcDevices": [
{
"PlcDeviceId": "Plc1",
"IpAddress": "127.0.0.1",
"Port": 1234,
"SlaveId": 1,
"DataPoints": [
{
"ModbusAddress": 0,
"EqpId": "eqp1"
},
{
"ModbusAddress": 0,
"EqpId": "eqp2"
}
]
},
{
"PlcDeviceId": "Plc2",
"IpAddress": "127.0.0.2",
"Port": 1234,
"SlaveId": "2",
"DataPoints": [
{
"ModbusAddress": 0,
"EqpId": "eqp3"
},
{
"ModbusAddress": 0,
"EqpId": "eqp4"
}
]
}
]对应poco对象为:
public class PlcDevice
{
public string IpAddress { get; set; } = "";
public int Port { get; set; } = 0;
public string PlcDeviceId { get; set; } = "";
public int SlaveId { get; set; }
public List<DataPoint> DataPoints { get; set; }
}
public class DataPoint
{ public int ModbusAddress { get; set; }
public string EqpId { get; set; } = "";
}读取 json 的C# 代码:
services.AddOptions();
//实例化一个对应 PlcDevices json 数组对象, 使用了 IConfiguration.Get<T>()
var PlcDeviceSettings= configuration.GetSection("PlcDevices").Get<List<PlcDevice>>();
//或直接通过 service.Configure<T>() 将appsettings 指定 section 放入DI 容器, 这里的T 为 List<PlcDevice>
services.Configure<List<PlcDevice>>(configuration.GetSection("PlcDevices"));到此这篇关于.Net6开发winform程序使用依赖注入的文章就介绍到这了。希望对大家的学习有所帮助，也希望大家多多支持编程网。
