NSArray NSMutableArray

 

注: iOS 6 新的快捷初始化写法:

NSArray:

NSArray *array = @[@"xiaoyu",@"yushuyi"];

NSMutableArray:

NSMutableArray *MArray = [@[@"xiaoyu",@"yushuyi"] mutableCopy];

1:使用Block遍历数据

NSArray *array = @[@"11",@"22"];
[array enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
    NSLog(@"%@ %d",obj,idx);
}];

注:为stop赋值为YES 可停止遍历.

2:带参数设定的Block遍历数据

[mArray enumerateObjectsWithOptions:  usingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
    NSLog(@"%@",obj);
}];

1:NSEnumerationConcurrent 以并发的方式遍历NSArray

2:NSEnumerationReverse     以逆向反向的方式遍历NSArray

3:Array 排序

NSArray *sortedArray = [dayDataMArrray sortedArrayUsingComparator: ^(id obj1, id obj2)
{
    NSDate *obj1Date = [NSDate Help_dateWithDateString: obj1 withDateFormat:@"yyyy-MM-dd"];
    NSDate *obj2Date = [NSDate Help_dateWithDateString: obj2 withDateFormat:@"yyyy-MM-dd"];
    if ([obj2Date timeIntervalSinceDate:obj1Date] > 0) {
        return (NSComparisonResult)NSOrderedAscending;
    }
    if ([obj2Date timeIntervalSinceDate:obj1Date] < 0) {
        return (NSComparisonResult)NSOrderedDescending;
    }
    return (NSComparisonResult)NSOrderedSame;
}];

注:

排序的理由是由开发者自行定义的.

灵活的返回 NSComparisonResult 即可达到任何排序效果.

4:让数组内的元素依次调用同一个方法

[[self.view subviews] makeObjectsPerformSelector:@selector(removeFromSuperview)];

也可以传参数:

- (void)makeObjectsPerformSelector:(SEL)aSelector withObject:(id)argument;