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NSMutableString*mstrOrigin = [[NSMutableString alloc]initWithString:@"mstrOriginValue"];
self.aCopyMStr= mstrOrigin;
self.strongMStr= mstrOrigin;
self.weakMStr= mstrOrigin;
NSLog(@"mstrOrigin輸出:%p,%@\\n", mstrOrigin,mstrOrigin);
NSLog(@"aCopyMStr輸出:%p,%@\\n",_aCopyMStr,_aCopyMStr);
NSLog(@"strongMStr輸出:%p,%@\\n",_strongMStr,_strongMStr);
NSLog(@"weakMStr輸出:%p,%@\\n",_weakMStr,_weakMStr);
NSLog(@"引用計數(shù)%@",[mstrOrigin valueForKey:@"retainCount"]);
//運行結(jié)果：
/*2017-07-27 14:49:51.279 WeakStrongCopyAssign[1371:59679] mstrOrigin輸出:0x608000271280,mstrOriginValue\n
2017-07-27 14:49:51.280 WeakStrongCopyAssign[1371:59679] aCopyMStr輸出:0x60800004cb10,mstrOriginValue\n
2017-07-27 14:49:51.280 WeakStrongCopyAssign[1371:59679] strongMStr輸出:0x608000271280,mstrOriginValue\n
2017-07-27 14:49:51.280 WeakStrongCopyAssign[1371:59679] weakMStr輸出:0x608000271280,mstrOriginValue\n
2017-07-27 14:49:51.280 WeakStrongCopyAssign[1371:59679] 引用計數(shù)2*/
// strongMStr和weakMStr指針指向的內(nèi)存地址都和mstrOrigin相同,但mstrOrigin內(nèi)存引用計數(shù)為2第喳，不為3冬阳，因為weakMStr雖然指向了數(shù)據(jù)內(nèi)存地址（之后用C簡稱呈宇，見示意圖1）秘血，但不會增加C計數(shù)即彪。copy修飾的的aCopyMStr紧唱，賦值后則是自己單獨開辟了一塊內(nèi)存，內(nèi)存上保存“mstrOrigin”字符串隶校，并指向漏益。
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