IOC、DI＜3＞ IServiceConllection 自定义IOC含属性注入、多实现注入，方法注入

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using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Threading.Tasks;namespace IOC.Common
{public class ZenServiceCollection : IZenServiceCollection{// 记录IOC注册的抽象、实现private Dictionary<string, Type> zenRelationship = new Dictionary<string, Type>();/// <summary>/// IOC容器映射关系注册   ===》  抽象 和具体/// </summary>/// <param name="serviceType">具体类</param>/// <param name="implementtationType">实现类</param>public void AddTransient(Type serviceType, Type implementtationType){this.zenRelationship.Add(serviceType.FullName, implementtationType);}/// <summary>/// 获取服务/// </summary>/// <typeparam name="T"></typeparam>/// <returns></returns>public T GetService<T>(){{//只限有无参构造函数， 若类没有构造函数，ctr会自动生成一个无参构造函数，但若定义了有参构造函数，就不会自动创建无参构造函数啦//Type t = zenRelationship[typeof(T).FullName];//return (T)Activator.CreateInstance(t);}{继续迭代 支持有参构造函数 ，只支持1个层级的有参构造函数  //Type t = zenRelationship[typeof(T).FullName];确定构造当前对象使用哪个构造函数（默认选择参数最多的构造函数）//ConstructorInfo[] ctors = t.GetConstructors();//ConstructorInfo ctor = ctors.OrderByDescending(c => c.GetParameters().Length).FirstOrDefault();//List<object> paralist = new List<object>();//foreach (ParameterInfo item in ctor.GetParameters())//{//    Type tt = item.ParameterType;//    Type ttt = item.GetType();//    Type t1 = zenRelationship[item.ParameterType.FullName];//    var target = Activator.CreateInstance(t1);//    paralist.Add(target);//}//return (T)Activator.CreateInstance(t, paralist.ToArray());}{继续迭代 支持有参构造函数   无线层级的//Type t = zenRelationship[typeof(T).FullName];//return (T)this.GetService(t);               }{//利用特性 指明构造函数创建  ，  默认是  使用 参数最多Type t = zenRelationship[typeof(T).FullName];return (T)this.GetService(t);}}private object GetService(Type type){#region 构造函数注入ConstructorInfo[] ctors = type.GetConstructors();ConstructorInfo ctor = ctors.Where(c=>c.IsDefined(typeof(SelectConstructAttribute),true)).FirstOrDefault();if (ctor==null){//当ctor不存在，则表示 构造函数没有对应特性标识ctor= ctors.OrderByDescending(c => c.GetParameters().Length).FirstOrDefault();}List<object> paralist = new List<object>();            foreach (ParameterInfo item in ctor.GetParameters()){Type t1 = zenRelationship[item.ParameterType.FullName];var target=this.GetService(t1);               paralist.Add(target);}#region  方法注入//构造对象object objInstance = Activator.CreateInstance(type, paralist.ToArray());           //获取对象的属性  只获取含有特性PropertyInjectionAttribute的属性foreach (MethodInfo item in type.GetMethods().Where(c => c.IsDefined(typeof(MethodInjectionAttribute), true))){List<object> paraOfMethodlist = new List<object>();foreach (ParameterInfo para in item.GetParameters()){Type t1 = zenRelationship[para.ParameterType.FullName];var target = this.GetService(t1);paraOfMethodlist.Add(target);}item.Invoke(objInstance, paraOfMethodlist.ToArray());}#endregion#endregion#region  属性注入           //获取对象的属性  只获取含有特性PropertyInjectionAttribute的属性foreach (PropertyInfo item in type.GetProperties().Where(c=>c.IsDefined(typeof(PropertyInjectionAttribute),true))){Type t1 = zenRelationship[item.PropertyType.FullName];var target = this.GetService(t1);item.SetValue(objInstance,target);}#endregionreturn objInstance;}}
}