使用NSComparator进行排序

如果我们想对自定义对象进行排序，我们需要提供NSComparator，它用于比较自定义对象。该块返回一个NSComparisonResult值来表示两个对象的排序。为了对整个数组进行排序，NSComparator的用法如下。

NSArray *sortedArray = [employeesArray sortedArrayUsingComparator:^NSComparisonResult(Employee *e1, Employee *e2){
    return [e1.firstname compare:e2.firstname];    
}];

使用NSSortDescriptor进行排序 让我们假设，作为一个例子，我们有一个包含自定义类实例的数组，Employee具有属性firstname, lastname和age。下面的例子说明了如何创建一个NSSortDescriptor，该NSSortDescriptor可用于按年龄键升序对数组内容进行排序。

NSSortDescriptor *ageDescriptor = [[NSSortDescriptor alloc] initWithKey:@"age" ascending:YES];
NSArray *sortDescriptors = @[ageDescriptor];
NSArray *sortedArray = [employeesArray sortedArrayUsingDescriptors:sortDescriptors];

使用自定义比较进行排序 名称是字符串，当您对字符串进行排序以呈现给用户时，您应该始终使用本地化比较。通常您还希望执行不区分大小写的比较。下面是一个示例，使用(localizedStandardCompare:)按姓氏和名字对数组进行排序。

NSSortDescriptor *lastNameDescriptor = [[NSSortDescriptor alloc]
              initWithKey:@"lastName" ascending:YES selector:@selector(localizedStandardCompare:)];
NSSortDescriptor * firstNameDescriptor = [[NSSortDescriptor alloc]
              initWithKey:@"firstName" ascending:YES selector:@selector(localizedStandardCompare:)];
NSArray *sortDescriptors = @[lastNameDescriptor, firstNameDescriptor];
NSArray *sortedArray = [employeesArray sortedArrayUsingDescriptors:sortDescriptors];

如需参考及详细讨论，请参考: https://developer.apple.com/library/ios/documentation/Cocoa/Conceptual/SortDescriptors/Articles/Creating.html http://www.ios-blog.co.uk/tutorials/objective-c/how-to-sort-nsarray-with-custom-objects/

我什么都试过了，但这个对我有用。在一个类中，我有另一个名为“crimeScene”的类，并希望通过“crimeScene”的属性进行排序。

这就像一个魅力:

NSSortDescriptor *sorter = [[NSSortDescriptor alloc] initWithKey:@"crimeScene.distance" ascending:YES];
[self.arrAnnotations sortUsingDescriptors:[NSArray arrayWithObject:sorter]];

在我的例子中，我使用“sortedArrayUsingComparator”对数组进行排序。请看下面的代码。

contactArray = [[NSArray arrayWithArray:[contactSet allObjects]] sortedArrayUsingComparator:^NSComparisonResult(ContactListData *obj1, ContactListData *obj2) {
    NSString *obj1Str = [NSString stringWithFormat:@"%@ %@",obj1.contactName,obj1.contactSurname];
    NSString *obj2Str = [NSString stringWithFormat:@"%@ %@",obj2.contactName,obj2.contactSurname];
    return [obj1Str compare:obj2Str];
}];

我的目标是，

@interface ContactListData : JsonData
@property(nonatomic,strong) NSString * contactName;
@property(nonatomic,strong) NSString * contactSurname;
@property(nonatomic,strong) NSString * contactPhoneNumber;
@property(nonatomic) BOOL isSelected;
@end

在Georg Schölly的第二个答案中有一个缺失的步骤，但它可以正常工作。

NSSortDescriptor *sortDescriptor;
sortDescriptor = [[[NSSortDescriptor alloc] initWithKey:@"birthDate"
                                              ascending:YES] autorelease];
NSArray *sortDescriptors = [NSArray arrayWithObject:sortDescriptor];
NSArray *sortedArray;
sortedArray = [drinkDetails sortedArrayUsingDescriptors:sortDescriptors];

//添加's'，因为我复制和粘贴时浪费了时间，在sortedArrayUsingDescriptors中没有's'就失败了

NSMutableArray *stockHoldingCompanies = [NSMutableArray arrayWithObjects:fortune1stock,fortune2stock,fortune3stock,fortune4stock,fortune5stock,fortune6stock , nil];

NSSortDescriptor *sortOrder = [NSSortDescriptor sortDescriptorWithKey:@"companyName" ascending:NO];

[stockHoldingCompanies sortUsingDescriptors:[NSArray arrayWithObject:sortOrder]];

NSEnumerator *enumerator = [stockHoldingCompanies objectEnumerator];

ForeignStockHolding *stockHoldingCompany;

NSLog(@"Fortune 6 companies sorted by Company Name");

    while (stockHoldingCompany = [enumerator nextObject]) {
        NSLog(@"===============================");
        NSLog(@"CompanyName:%@",stockHoldingCompany.companyName);
        NSLog(@"Purchase Share Price:%.2f",stockHoldingCompany.purchaseSharePrice);
        NSLog(@"Current Share Price: %.2f",stockHoldingCompany.currentSharePrice);
        NSLog(@"Number of Shares: %i",stockHoldingCompany.numberOfShares);
        NSLog(@"Cost in Dollars: %.2f",[stockHoldingCompany costInDollars]);
        NSLog(@"Value in Dollars : %.2f",[stockHoldingCompany valueInDollars]);
    }
    NSLog(@"===============================");

你必须创建sortDescriptor，然后你可以像下面这样使用sortDescriptor对nsmutablearray进行排序。

 let sortDescriptor = NSSortDescriptor(key: "birthDate", ascending: true, selector: #selector(NSString.compare(_:)))
 let array = NSMutableArray(array: self.aryExist.sortedArray(using: [sortDescriptor]))
 print(array)