这是一个很好的例子，让您轻松理解如何反转和反转注入装饰词。
我将按照以下每个步骤改进代码：
第1步：普通课
public class cart
{
private readonly idatabase _db;
private readonly ilogger _log;
private readonly iemailsender _es;
public cart()
{
_db = new database();
_log = new logger();
_es = new emailsender();
}
public void checkout(int orderid, int userid)
{
_db.save(orderid);
_log.loginfo("order has been checkout");
_es.sendemail(userid);
}
}
第2步：应用依赖注入
public cart(idatabase db, ilogger log, iemailsender es)
{
_db = db;
_log = log;
_es = es;
}
//dependency injection simple way
cart mycart = new cart(new database(),
new logger(), new emailsender());
//when you want to change new class. update here
mycart = new cart(new xmldatabase(),
new fakelogger(), new fakeemailsender());
第 3 步：应用依赖图绑定
//Create each Interface
DIContainer.SetModule<idatabase database>();
DIContainer.SetModule<ilogger logger>();
DIContainer.SetModule<iemailsender emailsender>();
DIContainer.SetModule<cart cart>();
//MyCart just need to use it
var myCart = DIContainer.GetModule();
public Cart()
{
_db = DIContainer.GetModule();
_log = DIContainer.GetModule();
_es = DIContainer.GetModule();
}
//When you want to change some module in Cart. Just need to change in where it define.
DIContainer.SetModule<idatabase xmldatabase>();`
</idatabase></cart></iemailsender></ilogger></idatabase>
