Answers:
最简单的方法是提供一个排序选择器(有关详细信息,请参见Apple的文档)
目标C
sortedArray = [anArray sortedArrayUsingSelector:@selector(localizedCaseInsensitiveCompare:)];
迅速
let descriptor: NSSortDescriptor = NSSortDescriptor(key: "YourKey", ascending: true, selector: "localizedCaseInsensitiveCompare:")
let sortedResults: NSArray = temparray.sortedArrayUsingDescriptors([descriptor])
Apple提供了几种用于字母排序的选择器:
compare:
caseInsensitiveCompare:
localizedCompare:
localizedCaseInsensitiveCompare:
localizedStandardCompare:
迅速
var students = ["Kofi", "Abena", "Peter", "Kweku", "Akosua"]
students.sort()
print(students)
// Prints "["Abena", "Akosua", "Kofi", "Kweku", "Peter"]"
此处提供的其他答案提到使用@selector(localizedCaseInsensitiveCompare:)
this可以很好地用于NSString数组,但是,如果要将其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,则应改为:
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:)];
name
这不是有效的键。使用NSSortDescriptor按字母顺序对字符串排序的键是什么?
排序NSString列表以使用诸如NSNumericSearch之类的功能的更强大方法:
NSArray *sortedArrayOfString = [arrayOfString sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2) {
return [(NSString *)obj1 compare:(NSString *)obj2 options:NSNumericSearch];
}];
与SortDescriptor结合使用,将得到如下结果:
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]];
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
)
排序字符串数组的另一种简单方法是使用NSString description
属性,方法是:
NSSortDescriptor *valueDescriptor = [NSSortDescriptor sortDescriptorWithKey:@"description" ascending:YES];
arrayOfSortedStrings = [arrayOfNotSortedStrings sortedArrayUsingDescriptors:@[valueDescriptor]];
对于大多数用途来说,这已经有了不错的答案,但是我将添加更具体的我的答案。
用英语,通常当我们按字母顺序排列时,我们会忽略短语开头的单词“ the”。因此,“美国”将在“ U”而不是“ T”下排序。
这为您做到了。
最好将它们归类。
// 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;
}
-(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];
}