//NSMutableArray 继承至 NSArray//        NSArray * array = @[];        //1.创建可变数组        NSMutableArray * array = [[NSMutableArray alloc] initWithCapacity:0];                //使用addObject 动态给数组中增加元素        /*        [array addObject:@"one"];        [array addObject:@"two"];        [array addObject:@"three"];        [array addObject:@"one"];         */        NSString * str1 = @"one";        NSString * str2 = @"two";        NSString * str3 = @"three";                //数组中可以存储,同一个对象多次        [array addObject:str1];        [array addObject:str2];        [array addObject:str3];        [array addObject:str1];                //2.指定对象插入的位置        [array insertObject:str1 atIndex:2];                //3.删除 会通过对象,删除数组中所有的同一个地址的对象        [array removeObject:str1];                //4.通过索引的方式删除对象,超出了数组的count值,那么就会导致异常 index beyond bounds        [array removeObjectAtIndex:0];                [array addObject:str2];        [array addObject:str3];        [array addObject:str1];                //5.删除数组中所有的元素        [array removeAllObjects];                        NSLog(@"array %@",array);                        [array addObject:str2];        [array addObject:str3];        [array addObject:str1];            //1.for换遍历        for (int i = 0; i < array.count; i++)        {            NSString * str = [array objectAtIndex:i];                        //在遍历数组的时候,千万不要给数组中,增加,或者删除元素//            [array removeObject:str1];                        NSLog(@"str %@",str);                  }                        //2.增强for循环        for (NSString * str in array)        {//            [array removeObject:str1];            //如果你在增强for循环中,删除元素,会直接导致异常出现            NSLog(@"str %@",str);        }                //3.枚举器                NSEnumerator * enumerator = [array objectEnumerator];        NSString * value;        while (value =http://www.mamicode.com/ [enumerator nextObject]) {            //如果你在枚举器中,删除元素,会直接导致异常出现//            [array removeObject:str1];            NSLog(@"str %@",value);        }                        //4.要通过遍历的方式确定删除哪个元素怎么办                NSMutableArray * array2 = [[NSMutableArray alloc] init];        [array2 addObject:@"1"];        [array2 addObject:@"2"];        [array2 addObject:@"3"];        [array2 addObject:@"4"];        [array2 addObject:@"5"];                NSMutableArray * tmp = [[NSMutableArray alloc] init];                for (NSString * str in array2)        {            if ([str isEqualToString:@"3"])            {                [tmp addObject:str];            }        }                NSLog(@"array2 %@",array2);        NSLog(@"tmp %@",tmp);                        //遍历临时数组        for (int i = 0; i < tmp.count; i++)        {            NSString * str = [tmp objectAtIndex:i];                        //从原数组中删除,临时数组中存储的对象            [array2 removeObject:str];        }                NSLog(@"array2 %@",array2);