依赖注入
由容器统一创建对象并管理其创建对象的生命周期;
AddTransient瞬时服务
每次使用都会创建新的实例
AddScoped作用域
容器或子容器的生命周期内,对象保持一致,如果容器释放掉,那就意味着对象也会释放掉;
AddSingleton单例
整个根容器的生命周期内是同一个对象
其他
TryAddScoped
AddHttpClient
AddHttpContextAccessor//请求管道
AddDbContext //EF CORE
AddControllers
批量注入
var assembly = Assembly.GetExecutingAssembly();
var ilist = assembly.GetTypes().Where(t => t.GetTypeInfo().IsInterface);
var list = assembly.GetTypes().Where(t => t.GetTypeInfo().IsClass);
foreach (Type serviceType in list)
{
var interfaceType = ilist.FirstOrDefault(x => x.IsAssignableFrom(serviceType));
if (interfaceType != null)
{
services.AddScoped(interfaceType, serviceType);
}
}
其他生命周期中获取服务
private readonly IServiceProvider _serviceProvider;
public Test(IServiceProvider serviceProvider)
{
_serviceProvider = serviceProvider;
}
public void test1()
{
using(var scope = this._serviceProvider.CreateScope())
{
//.NetCore 中IServiceProvider的 GetService()和GetRequiredService()之间的区别
//GetService- 如果服务未注册,则返回null
//GetRequiredService- 如果服务未注册,则抛出一个Exception异常
var appointmentService = scope.ServiceProvider.GetService<IAppointmentService>();
}
}
中间件
系统自带
UseHttpsRedirection:强制https跳转
....
用途:
- 全局拦截,如:IP白名单,请求头过滤
- 错误处理,如:未处理异常处理、自定义异常(登录失败,参数错误等)处理
- 权限校验
- 。。。
配置文件application.json
读取方式:
Configuration["A"]
Configuration["Serilog:LogPath"]
Configuration.GetValue<bool>("DetailedErrors")
Configuration.GetConnectionString("KKBMConnection")
Configuration.Get<TOption>("")
选项模式
public class PositionOptions
{
public const string Position = "Position";
public string Title { get; set; } = String.Empty;
public string Name { get; set; } = String.Empty;
}
using ConfigSample.Options;
var builder = WebApplication.CreateBuilder(args);
builder.Services.Configure<PositionOptions>(
builder.Configuration.GetSection(PositionOptions.Position));
var app = builder.Build();
IOptions、IOptionsMonitor以及IOptionsSnapshot的区别
配置项目启动地址
- 修改launchSettings.json
- builder.WebHost.UseUrls("http://0.0.0.0:5552", "https://127.0.0.1:5553", "https://localhost:5554")
- app.Urls.Add("http://*:6666");app.Urls.Add("http://+:8888");app.Urls.Add("http://0.0.0.0:9999");
WebApi
ActionResult返回类型
return result;
return Ok(result);//200
return BadRequest(result);/400
CORS允许跨域请求
builder.Services.AddCors(options =>
{
options.AddPolicy("cors", policy =>
{
policy.AllowAnyHeader()
.AllowAnyMethod()
.AllowCredentials()
.WithOrigins("https://www.kkbmtj.com", "http://webadmin.kkbmtj.com", "https://webadmin.kkbmtj.com");
});
});
//......
var app = builder.Build();
app.UseCors("cors");
System.Text.Json API
.netcore 中,尽量使用Syetem.Text.Json来序列化JSON,官方地址:System.Text.Json 序列化与反序列化
JsonSerializer.Serialize(obj)
JsonSerializer.Deserialize<T>(string)
jsonSerializer.PropertyNamingPolicy = JsonNamingPolicy.CamelCase;//驼峰规则
jsonSerializer.PropertyNameCaseInsensitive = true;//是否区分大小写
jsonSerializer.Converters.Add(new SystemTextJsonConvert.DateTimeConverter());//自定义时间序列化
jsonSerializer.Converters.Add(new SystemTextJsonConvert.DateTimeNullableConverter());
jsonSerializer.Converters.Add(new SystemTextJsonConvert.LongToStringConverter());
jsonSerializer.Converters.Add(new SystemTextJsonConvert.LongNullToStringConverter());
jsonSerializer.Encoder = JavaScriptEncoder.Create(UnicodeRanges.All);//解析格式,兼容中文
jsonSerializer.DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull;//忽略null值
public class DateTimeConverter : JsonConverter<DateTime>
{
public override DateTime Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
{
return DateTime.Parse(reader.GetString());
}
public override void Write(Utf8JsonWriter writer, DateTime value, JsonSerializerOptions options)
{
writer.WriteStringValue(value.ToString("yyyy-MM-dd HH:mm:ss"));
}
}
进阶
JsonDocument
JsonElement
JsonSerializer.DeserializeAsync(Stream)
HttpClient
官方文档:在 ASP.NET Core 中使用 IHttpClientFactory 发出 HTTP 请求
注入服务:Service.AddHttpClient();