initWithKey:ascending:

キーと昇降順でソートデスクリプタを初期化して返します

-(id)initWithKey:(NSString *)key:
             ascending:(BOOL)ascending:

解説

キーと昇降順でソートデスクリプタを初期化して返します。

返り値

( id )

オブジェクト（ソートデスクリプタ）

引数

( NSString * )key

( BOOL )ascending

フレームワーク

Foundation

クラス

NSSortDescriptor

Instance Methods

使用可能

10.3

参照

-initWithKey:ascending:selector:

例文

NSDictionaryをソートする

#pragma mark initWithKey:
-(void)method001
{

    NSMutableArray *arr = [NSMutableArray arrayWithCapacity:0];
    
    NSMutableDictionary *dic1 = 
            [NSMutableDictionary dictionaryWithObjectsAndKeys:
                @"aaa4",@"key1",@"bbb1",@"key2",@"ccc1",@"key3",nil];
    NSMutableDictionary *dic2 = 
            [NSMutableDictionary dictionaryWithObjectsAndKeys:
                @"aaa2",@"key1",@"bbb2",@"key2",@"ccc2",@"key3",nil];
    NSMutableDictionary *dic3 = 
            [NSMutableDictionary dictionaryWithObjectsAndKeys:
                @"aaa1",@"key1",@"bbb3",@"key2",@"ccc3",@"key3",nil];
    NSMutableDictionary *dic4 = 
            [NSMutableDictionary dictionaryWithObjectsAndKeys:
                @"aaa3",@"key1",@"bbb4",@"key2",@"ccc4",@"key3",nil];
    
    [arr addObject: dic1 ];
    [arr addObject: dic2 ];
    [arr addObject: dic3 ];
    [arr addObject: dic4 ];
    
    NSSortDescriptor *descriptor=[[NSSortDescriptor alloc] initWithKey:@"key1" 
                                                              ascending:YES];
    
    NSArray *sortedArray = [arr sortedArrayUsingDescriptors:[NSArray arrayWithObject:descriptor]] ;

    NSLog(@"%s %@,%@,%@,%@",__FUNCTION__,[[arr objectAtIndex:0] objectForKey:@"key1"],
                                [[arr objectAtIndex:1] objectForKey:@"key1"],
                                [[arr objectAtIndex:2] objectForKey:@"key1"],
                                [[arr objectAtIndex:3] objectForKey:@"key1"]);
    //=>-[OOOAppDelegate method001] aaa4,aaa2,aaa1,aaa3
    
    NSLog(@"%s %@,%@,%@,%@",__FUNCTION__,[[sortedArray objectAtIndex:0] objectForKey:@"key1"],
                                [[sortedArray objectAtIndex:1] objectForKey:@"key1"],
                                [[sortedArray objectAtIndex:2] objectForKey:@"key1"],
                                [[sortedArray objectAtIndex:3] objectForKey:@"key1"]);
    
    //=>-[OOOAppDelegate method001] aaa1,aaa2,aaa3,aaa4

}

クラスをソートする

#pragma mark initWithKey:
//クラスをソートする
/* 
//CustomClass.h
#import <UIKit/UIKit.h>
 @interface CustomClass : NSObject
{
NSString *customClassValue;
}

@property (retain) NSString *customClassValue;

@end
 //CustomClass.m
 #import "CustomClass.h"
 
 @implementation CustomClass
 
 @synthesize customClassValue;
 
 -(NSString *)description
 {
 return customClassValue;
 
 }
 @end

 */
-(void)method002
{
    NSMutableArray *arr = [NSMutableArray arrayWithCapacity:0];
    
    CustomClass *obj1 = [[CustomClass alloc] init];
    [obj1 setCustomClassValue:@"aaa4"];
    CustomClass *obj2 = [[CustomClass alloc] init];
    [obj2 setCustomClassValue:@"aaa2"];
    CustomClass *obj3 = [[CustomClass alloc] init];
    [obj3 setCustomClassValue:@"aaa1"];
    CustomClass *obj4 = [[CustomClass alloc] init];
    [obj4 setCustomClassValue:@"aaa3"];

    [arr addObject: obj1 ];
    [arr addObject: obj2 ];
    [arr addObject: obj3 ];
    [arr addObject: obj4 ];
    
    NSSortDescriptor *descriptor=[[NSSortDescriptor alloc] initWithKey:@"customClassValue" 
                                                             ascending:YES];
    
    NSArray *sortedArray = [arr sortedArrayUsingDescriptors:[NSArray arrayWithObject:descriptor]] ;
    NSLog(@"%s %@",__FUNCTION__,[arr description]);
    //=>-[OOOAppDelegate method002] (aaa4,aaa2,aaa1,aaa3)
    NSLog(@"%s %@",__FUNCTION__,[sortedArray description]);
    //=>-[OOOAppDelegate method002] (aaa1,aaa2,aaa3,aaa4)
    
}