学步园

Lazy<T> allow us to load a class deferred. Or we can provide a Deferred Load function or loading factory to load it.

Main class Entry(with Lazy<T>): 

namespace ConsoleLazyLoad<br /> {<br /> class Program<br /> {<br /> static void Main(string[] args)<br /> {<br /> //Lazy<ObjService> lazyObjServ = new Lazy<ObjService>();<br /> //Lazy<ObjService> lazyObjServ = new Lazy<ObjService>(()=>new ObjService(new ObjDal("new Test")));<br /> //Lazy<ObjService> lazyObjServ = new Lazy<ObjService>(valfactory);<br /> Lazy<ObjService> lazyObjServ = new Lazy<ObjService>(() => { var a = new ObjDal("dal2"); return new ObjService(a); });<br /> Console.WriteLine(lazyObjServ.Value.Name);<br /> Console.WriteLine(lazyObjServ.Value.Dal.Name);</p> <p> Console.ReadKey();<br /> }<br /> static Func<ObjService> valfactory = new Func<ObjService>(ThisFactory);<br /> static ObjService ThisFactory()<br /> {<br /> var a = new ObjDal("Test Funct");<br /> return new ObjService(a);<br /> }<br /> }<br /> }<br />

ObjService.cs

namespace ConsoleLazyLoad<br /> {<br /> public class ObjService<br /> {<br /> public string Name { get; set; }<br /> public ObjDal Dal { get; private set; }</p> <p> public ObjService()<br /> {<br /> Dal = new ObjDal("Default");<br /> Name = "Default";<br /> }<br /> public ObjService(ObjDal _dal)<br /> {<br /> Dal = _dal;<br /> Name = Dal.Name;<br /> }<br /> }<br /> public class ObjDal<br /> {<br /> public string Name { get;set;}</p> <p> public ObjDal()<br /> {<br /> }</p> <p> public ObjDal(string _name)<br /> {<br /> Name = _name;<br /> }<br /> }<br /> }<br />