ifinder

; addnewcontactl (* contact );Contactdb-> setowncardl (* contact );Cleanupstack: popanddestroy (2 ); Example 5 search for and update address book entries This example is complex and involves the findasyncl lookup function. Such function instances include:Ccontactidarray * ccontactdatabase: findlc (const tdesc atext, const ccontactitemfielddef * afielddef );Cidlefinder * ccontactdatabase: findasyncl (const tdesc atext, const ccontactitemfielddef * afielddef, midlefindobserver * aobserver );

subject to covariant. // Declare the Find Find // Declare the Find Find Iv. Coordination and inverter in generic interfaces: The covariant inversion in the generic interface is very similar to that in the generic delegate, but the angle brackets of the generic definition are changed to the interface definition. 1. Inverter in generic Interfaces The following interface definition: Public interface IFeedable { Void Feed (T t ); } An in keyword exists before the interface generic

generic InterfacesThe following interface definition:Copy codeThe Code is as follows:Public interface IFinder {T Find ();}The out keyword is used before the generic T of a generic interface to indicate that this interface may be subject to covariant. the following generic interface implementation classCopy codeThe Code is as follows:Public class Finder {Public T Find (){Return new T ();}}// Use covariant. The generic type of

the FeedImp 2. covariant in generic InterfacesThe following interface definition:Copy codeThe Code is as follows: public interface IFinder {T Find ();} The out keyword is used before the generic T of a generic interface to indicate that this interface may be subject to covariant. the following generic interface implementation classCopy codeThe Code is as follows: public class Finder {Public T Find (){Return new T ();}}// Use covariant. The generic ty

Return False ; 25 } 26 } 27 } Start searching here: 1 Ipoint temppoint = New Ipoint ( 1 , 2 ); 2 Finder ifinder = New Finder (temppoint ); 3 Ipoint findres = Closedlist. Find ( New Predicate Ipoint > (Ifinder. findcurrentpoint )); OK. Here we find the ipoint object of Y = 1, x = 2.Sort ()We need to first create a class that inherits from icomparer Public

interface inversion: ifeedable Dog ; feeddog = new feedimp Animal ; (); The code above // assigns the feedimp 2. Covariance in generic interfacesC # codeCopy//Definition of the interface:Public InterfaceIfinderOutT> {T Find ();} The // generic interface's generic t was preceded by an out keyword to indicate that this interface is likely to be covariant; The following generic interface implementation class public class Finder T ; :