數組排序

1、使用sortedArrayUsingSelector

NSArray *array = @[@“天”，@“地”，@“玄”，@“黃”，nil];

NSArray *array1 = [array sortedArrayUsingSelector:@selector(compare:)];

2.block方式排序

[array sortedArrayUsingComparator:^NSComprisonResult(id object1，id object2){

NSComparisonResult retuslt = [obj1 compare:obj2];

Return retuslt;

];