csharp
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);
}
#endregion
return objInstance;
}
}
}