OC-数组

    1.创建可变数组

NSMutableArray *array = [[NSMutableArray alloc] init];NSMutableArray *array = [NSMutableArray array];

2.创建有对象数组

NSMutableArray *array = [[NSMutableArray alloc]initWithObjects:@"data1",@"data2",nil];

<span style="font-family: Arial, Helvetica, sans-serif;">NSMutableArray *</span>array = [NSMutableArray arrayWithObject:@"data3"];

array = [NSMutableArray arrayWithObjects:@"d1",@"d2".@"d3", nil];

3.添加元素

 [array addObject:对象];

 [array insertObject:@"nihao" atIndex:0];

4.根据下标取值

[array objectAtIndex: 下标];     NSString *firstObj = [array objectAtIndex:0];