ios特性访问器方法（setter和getter）

Employee.h

@interface Employee:NSObject

{

　　int _employeeNumber;

　　NSString *_name;

　　Employee*_supervisitor;

　　int _salary;

}

@property int employeeNumber;

@property(nonatomic,retain) NSString * name;

@property(nonatomic,retain)Employee *supervisitor;

@property int salary;

......

@end

Employee.m

@implementation Employee

@synthesize employeeNumber;

@synthesize name;

//@synthesize supervistor;//在这不要实现setter和getter下面手动实现

@synthesize salary;

-(void)setSupervistor:(Employee *)newSupervisitor

{

　　[newSupervistor retain];

　　[_supervistor release];

　　_supervistor=newSupervisitor;

}

-(Employee*)supervisitor

{

　　return _supervisitor;

}

//上面代码解释：上面代码的顺序很重要。向存储在supervisitor中的当前对象发送一条release消息，会对应当存储它的时候所接受的一条retain消息