Student.h:

#import <Foundation/Foundation.h>  @interface Student : NSObject @property(nonatomic,assign) int age; +(id)studentWithAge:(int)age; @end

Student.m:

#import "Student.h"  @implementation Student +(id)studentWithAge:(int)age{     Student *stu=[[[Student alloc] init] autorelease];     stu.age=age;     return stu; } -(void)dealloc{     NSLog(@"Age=%i对象被释放",_age);     [super dealloc]; } @end

main:

#import <Foundation/Foundation.h> #import "Student.h" void arrayCreate(){     NSMutableArray *array=[NSMutableArray arrayWithObject:@"1"];     //添加成员     [array addObject:@"2"];     [array addObject:@"3"];     //删除成员     [array removeObject:@"2"];     [array removeLastObject];     [array removeAllObjects];          NSLog(@"动态数组是：%@",array); } #pragma mark - 数组内存的管理 void arrayMemory(){     NSMutableArray * array=[NSMutableArray array];     Student *stu1=[Student studentWithAge:16];     Student *stu2=[Student studentWithAge:22];     //注意：array进行添加元素的时候，会对被添加的元素执行一次retain操作，计数器加1     [array addObject:stu1];//注意：执行这句话之后，首先先对stu1进行一次retain操作，计数器加1     [array addObject:stu2];     NSLog(@"addStu->计数器%i",[stu1 retainCount]);     //注意：array进行删除元素的时候，会对被删除的元素执行一次release操作，计数器减1     [array removeObject:stu1];//执行这句之后，stu1进行一次release操作，计数器减1     NSLog(@"removeStu->计数器%i",[stu1 retainCount]);     //注意：当数组被释放的时候，会对有所由成员进行一次release操作 } #pragma mark - 替换元素 void arrayReplase(){     NSMutableArray *array=[NSMutableArray arrayWithObjects:@"1",@"2",@"3",@"4",nil];  //只能塞OC对象     //替换元素     [array replaceObjectAtIndex:1 withObject:@"8"];     Student *stu1=[Student studentWithAge:16];     [array replaceObjectAtIndex:2 withObject:stu1];//随便塞对象，可以替换一个stu对象     NSLog(@"array:%@",array); } #pragma mark - 排序 void arraySort(){     NSMutableArray *array=[NSMutableArray arrayWithObjects:@"1",@"4",@"3",@"2",nil];  //只能塞OC对象     NSLog(@"排序前：%@",array);     [array sortUsingSelector:@selector(compare:)];     NSLog(@"排序后：%@",array);      } int main(int argc, const char * argv[]) {      @autoreleasepool {                  /*arrayCreate();         arrayMemory();         arrayReplase();*/         arraySort();     }     return 0; }

结果：

2013-08-02 15:32:46.883 NSMutableArray[1179:303] 排序前：(

    1,

    4,

    3,

    2

)

2013-08-02 15:32:46.885 NSMutableArray[1179:303] 排序后：(

    1,

    2,

    3,

    4

)