//联系人:石虎QQ: 1224614774昵称:嗡嘛呢叭咪哄
一、集合&不可变
集合类对象是指NSArray、NSDictionary、NSSet ... 之类的对象。
NSArray* arr =@[@[@"a",@"b"], [@[@"c",@"d"]mutableCopy],@"AA", [NSMutableStringstringWithString:@"a"]];
NSArray*arrCy = [arrcopy];
NSMutableArray*arrMCy = [arrmutableCopy];
//!分别打印变量的内存地址及对象地址
NSLog(@" arr :%p %p [%p %p %p %p]", arr, &arr, arr[0], arr[1], arr[2], arr[3]);
NSLog(@" arrCy :%p %p [%p %p %p %p]", arrCy, &arrCy, arrCy[0], arrCy[1], arrCy[2], arrCy[3]);
NSLog(@"arrMCy :%p %p [%p %p %p %p]", arrMCy, &arrMCy, arrMCy[0], arrMCy[1], arrMCy[2], arrMCy[3]);
//!输出
arr :0x1004034300x7fff5fbff7a0[0x1004012600x1004032a00x1000010d80x1004033a0]
arrCy :0x1004034300x7fff5fbff798[0x1004012600x1004032a00x1000010d80x1004033a0]
arrMCy :0x1004034f00x7fff5fbff790[0x1004012600x1004032a00x1000010d80x1004033a0]
从打印结果结论:
浅拷贝 :操作是不可变集合的copy
单层深拷贝:操作是拷贝不可变集合的mutableCopy
集合内部的元素仍然是浅拷贝,无论该元素是否是集合是否可变
二、集合&可变
NSMutableArray* arr = [NSMutableArray arrayWithObjects:@[@"a",@"b"], [NSMutableArray arrayWithObject:@"A"],@"AA", [NSMutableString stringWithString:@"a"],nil];
NSArray* arrCy = [arr copy];
NSMutableArray* arrMCy = [arr mutableCopy];
NSLog(@" arr :%p %p [%p %p %p %p]", arr, &arr, arr[0], arr[1], arr[2], arr[3]);
NSLog(@" arrCy :%p %p [%p %p %p %p]", arrCy, &arrCy, arrCy[0], arrCy[1], arrCy[2], arrCy[3]);
NSLog(@"arrMCy :%p %p [%p %p %p %p]", arrMCy, &arrMCy, arrMCy[0], arrMCy[1], arrMCy[2], arrMCy[3]);
arr :0x1005023d00x7fff5fbff7d0[0x1005000d00x1005021400x1000010b80x100502320]
arrCy :0x1005025000x7fff5fbff7c8[0x1005000d00x1005021400x1000010b80x100502320]
arrMCy :0x1005025c00x7fff5fbff7c0[0x1005000d00x1005021400x1000010b80x100502320]
可以看出
可变集合的copy和mutableCopy都是单层深拷贝
集合拷贝结论
集合copymutableCopy
不可变对象浅单层深
可变对象单层深单层深
