按键值对字典数组进行排序

Question

假设我有一个包含6个字典的数组 - 每个字典都有一个“位置”键，其中包含相关值。我怎样才能将这些价值观排在一起，这样我才能从中得到......

"location" : USA
"location" : UK
"location" : Asia
"location" : UK
"location" : USA
"location" : Asia

到此？

"location" : Asia
"location" : Asia
"location" : UK
"location" : UK
"location" : USA
"location" : USA

Answer 1

我想sortedArrayUsingComparator:方法就是您要找的方法：

NSArray *array = @[@{@"location" : @"USA"},
                   @{@"location" : @"UK"},
                   @{@"location" : @"Asia"},
                   @{@"location" : @"UK"},
                   @{@"location" : @"USA"},
                   @{@"location" : @"Asia"}];
NSArray *sortedArray = [array sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2) {
    return [[obj1 valueForKey:@"location"] compare:[obj2 valueForKey:@"location"]];
}];