如何按字母顺序对NSArray进行排序？

Question

如何将填充了[UIFont familyNames]的数组按字母顺序排序？

Answer 1

最简单的方法是提供排序选择器（Apple's documentation以获取详细信息）

<强>目标C

sortedArray = [anArray sortedArrayUsingSelector:@selector(localizedCaseInsensitiveCompare:)];

<强>夫特

let descriptor: NSSortDescriptor = NSSortDescriptor(key: "YourKey", ascending: true, selector: "localizedCaseInsensitiveCompare:")
let sortedResults: NSArray = temparray.sortedArrayUsingDescriptors([descriptor])

---

Apple为字母排序提供了几个选择器：

• compare:
• caseInsensitiveCompare:
• localizedCompare:
• localizedCaseInsensitiveCompare:
• localizedStandardCompare:

<强>夫特

var students = ["Kofi", "Abena", "Peter", "Kweku", "Akosua"]
students.sort()
print(students)
// Prints "["Abena", "Akosua", "Kofi", "Kweku", "Peter"]"

Reference

Answer 2

此处提供的其他答案提及使用@selector(localizedCaseInsensitiveCompare:) 这适用于NSString数组，但是如果你想将它扩展到另一种类型的对象，并根据'name'属性对这些对象进行排序，你应该这样做：

NSSortDescriptor *sort = [NSSortDescriptor sortDescriptorWithKey:@"name" ascending:YES];
sortedArray=[anArray sortedArrayUsingDescriptors:@[sort]];

您的对象将根据这些对象的name属性进行排序。

如果您希望排序不区分大小写，则需要像这样设置描述符

NSSortDescriptor *sort = [NSSortDescriptor sortDescriptorWithKey:@"name" ascending:YES selector:@selector(caseInsensitiveCompare:)];

Answer 3

一种更强大的方法，可以对NSString列表进行排序，以使用NSNumericSearch：

之类的东西

NSArray *sortedArrayOfString = [arrayOfString sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2) {
            return [(NSString *)obj1 compare:(NSString *)obj2 options:NSNumericSearch];
        }];

结合SortDescriptor，可以得到类似的结果：

NSSortDescriptor *sort = [NSSortDescriptor sortDescriptorWithKey:@"name" ascending:YES comparator:^NSComparisonResult(id obj1, id obj2) {
        return [(NSString *)obj1 compare:(NSString *)obj2 options:NSNumericSearch];
    }];
NSArray *sortedArray = [anArray sortedArrayUsingDescriptors:[NSArray arrayWithObject:sort]];

Answer 4

使用以下代码按字母顺序排序：

    NSArray *unsortedStrings = @[@"Verdana", @"MS San Serif", @"Times New Roman",@"Chalkduster",@"Impact"];

    NSArray *sortedStrings =
    [unsortedStrings sortedArrayUsingSelector:@selector(compare:)];

    NSLog(@"Unsorted Array : %@",unsortedStrings);        
    NSLog(@"Sorted Array : %@",sortedStrings);

以下是控制台日志：

2015-04-02 16:17:50.614 ToDoList[2133:100512] Unsorted Array : (
    Verdana,
    "MS San Serif",
    "Times New Roman",
    Chalkduster,
    Impact
)

2015-04-02 16:17:50.615 ToDoList[2133:100512] Sorted Array : (
    Chalkduster,
    Impact,
    "MS San Serif",
    "Times New Roman",
    Verdana
)

Answer 5

另一种对字符串数组进行排序的简单方法是使用NSString description属性：

NSSortDescriptor *valueDescriptor = [NSSortDescriptor sortDescriptorWithKey:@"description" ascending:YES];
arrayOfSortedStrings = [arrayOfNotSortedStrings sortedArrayUsingDescriptors:@[valueDescriptor]];

Answer 6

对于大多数用途，这已经有了很好的答案，但我会添加更具体的。

在英语中，通常在我们按字母顺序排列时，我们会忽略单词＆＃34;＆＃34;在短语的开头。那么＆＃34;美国＆＃34;将按照＆＃34; U＆＃34;而不是＆＃34; T＆＃34;。

这样做适合你。

将这些列入类别可能是最好的。

// Sort an array of NSStrings alphabetically, ignoring the word "the" at the beginning of a string.

-(NSArray*) sortArrayAlphabeticallyIgnoringThes:(NSArray*) unsortedArray {

    NSArray * sortedArray = [unsortedArray sortedArrayUsingComparator:^NSComparisonResult(NSString* a, NSString* b) {

        //find the strings that will actually be compared for alphabetical ordering
        NSString* firstStringToCompare = [self stringByRemovingPrecedingThe:a];
        NSString* secondStringToCompare = [self stringByRemovingPrecedingThe:b];

        return [firstStringToCompare compare:secondStringToCompare];
    }];
    return sortedArray;
}

// Remove "the"s, also removes preceding white spaces that are left as a result. Assumes no preceding whitespaces to start with. nb: Trailing white spaces will be deleted too.

-(NSString*) stringByRemovingPrecedingThe:(NSString*) originalString {
    NSString* result;
    if ([[originalString substringToIndex:3].lowercaseString isEqualToString:@"the"]) {
        result = [[originalString substringFromIndex:3] stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];
    }
    else {
        result = originalString;
    }
    return result;
}

Answer 7

-(IBAction)SegmentbtnCLK:(id)sender
{ [self sortArryofDictionary];
    [self.objtable reloadData];}
-(void)sortArryofDictionary
{ NSSortDescriptor *sorter;
    switch (sortcontrol.selectedSegmentIndex)
    {case 0:
            sorter=[[NSSortDescriptor alloc]initWithKey:@"Name" ascending:YES];
            break;
        case 1:
            sorter=[[NSSortDescriptor alloc]initWithKey:@"Age" ascending:YES];
            default:
            break; }
    NSArray *sortdiscriptor=[[NSArray alloc]initWithObjects:sorter, nil];
    [arr sortUsingDescriptors:sortdiscriptor];
    }