ios 排序汇总

ios 排序汇总 

IOS几种简单有效的数组排序方法

//第一种，利用数组的sortedArrayUsingComparator调用 NSComparator ，obj1和obj2指的数组中的对象

NSComparator cmptr = ^(id obj1, id obj2){ 
 if ([obj1 integerValue] > [obj2 integerValue]) { 
        return (NSComparisonResult)NSOrderedDescending; 
    } 
  
    if ([obj1 integerValue] < [obj2 integerValue]) { 
        return (NSComparisonResult)NSOrderedAscending; 
    } 
    return (NSComparisonResult)NSOrderedSame; 
}; 
NSArray *sortArray = [[NSArray alloc] initWithObjects:@"1",@"3",@"4",@"7",@"8",@"2",@"6",@"5",@"13",@"15",@"12",@"20",@"28",@"",nil]; 
 //排序前 
 NSMutableString *outputBefore = [[NSMutableString alloc] init]; 
 for(NSString *str in sortArray){ 
  [outputBefore appendFormat:@"]; 
 } 
 NSLog(@"排序前:%@",outputBefore); 
 [outputBefore release]; 
 //第一种排序 
 NSArray *array = [sortArray sortedArrayUsingComparator:cmptr]; 
  
 NSMutableString *outputAfter = [[NSMutableString alloc] init]; 
 for(NSString *str in array){ 
  [outputAfter appendFormat:@"]; 
 } 
 NSLog(@"排序后:%@",outputAfter); 
 [outputAfter release];

NSComparator cmptr = ^(id obj1, id obj2){
 if ([obj1 integerValue] > [obj2 integerValue]) {
        return (NSComparisonResult)NSOrderedDescending;
    }
 
    if ([obj1 integerValue] < [obj2 integerValue]) {
        return (NSComparisonResult)NSOrderedAscending;
    }
    return (NSComparisonResult)NSOrderedSame;
};
NSArray *sortArray = [[NSArray alloc] initWithObjects:@"1",@"3",@"4",@"7",@"8",@"2",@"6",@"5",@"13",@"15",@"12",@"20",@"28",@"",nil];
 //排序前
 NSMutableString *outputBefore = [[NSMutableString alloc] init];
 for(NSString *str in sortArray){
  [outputBefore appendFormat:@"];
 }
 NSLog(@"排序前:%@",outputBefore);
 [outputBefore release];
 //第一种排序
 NSArray *array = [sortArray sortedArrayUsingComparator:cmptr];
 
 NSMutableString *outputAfter = [[NSMutableString alloc] init];
 for(NSString *str in array){
  [outputAfter appendFormat:@"];
 }
 NSLog(@"排序后:%@",outputAfter);
 [outputAfter release];

第二种 排序方法 利用sortedArrayUsingFunction 调用 对应方法customSort，这个方法中的obj1和obj2分别是指数组中的对象。

[plain]
NSInteger customSort(id obj1, id obj2,void* context){ 
 if ([obj1 integerValue] > [obj2 integerValue]) { 
        return (NSComparisonResult)NSOrderedDescending; 
    } 
  
    if ([obj1 integerValue] < [obj2 integerValue]) { 
        return (NSComparisonResult)NSOrderedAscending; 
    } 
    return (NSComparisonResult)NSOrderedSame; 
} 
 NSArray *sortArray = [[NSArray alloc] initWithObjects:@"1",@"3",@"4",@"7",@"8",@"2",@"6",@"5",@"13",@"15",@"12",@"20",@"28",@"",nil]; 
 //排序前 
 NSMutableString *outputBefore = [[NSMutableString alloc] init]; 
 for(NSString *str in sortArray){ 
  [outputBefore appendFormat:@"]; 
 } 
 NSLog(@"排序前:%@",outputBefore); 
 [outputBefore release]; 
  
 NSArray *array = [sortArray sortedArrayUsingFunction:customSort context:nil]; 
  
 NSMutableString *outputAfter = [[NSMutableString alloc] init]; 
 for(NSString *str in array){ 
  [outputAfter appendFormat:@"]; 
 } 
 NSLog(@"排序后:%@",outputAfter); 
 [outputAfter release];

NSInteger customSort(id obj1, id obj2,void* context){
 if ([obj1 integerValue] > [obj2 integerValue]) {
        return (NSComparisonResult)NSOrderedDescending;
    }
 
    if ([obj1 integerValue] < [obj2 integerValue]) {
        return (NSComparisonResult)NSOrderedAscending;
    }
    return (NSComparisonResult)NSOrderedSame;
}
 NSArray *sortArray = [[NSArray alloc] initWithObjects:@"1",@"3",@"4",@"7",@"8",@"2",@"6",@"5",@"13",@"15",@"12",@"20",@"28",@"",nil];
 //排序前
 NSMutableString *outputBefore = [[NSMutableString alloc] init];
 for(NSString *str in sortArray){
  [outputBefore appendFormat:@"];
 }
 NSLog(@"排序前:%@",outputBefore);
 [outputBefore release];
 
 NSArray *array = [sortArray sortedArrayUsingFunction:customSort context:nil];
 
 NSMutableString *outputAfter = [[NSMutableString alloc] init];
 for(NSString *str in array){
  [outputAfter appendFormat:@"];
 }
 NSLog(@"排序后:%@",outputAfter);
 [outputAfter release];

第三种 利用sortUsingDescriptors调用NSSortDescriptor

[plain]
NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"price" ascending:NO];//其中，price为数组中的对象的属性，这个针对数组中存放对象比较更简洁方便 
  NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:&sortDescriptor count:1]; 
  [_totalInfoArray sortUsingDescriptors:sortDescriptors]; 
  [_airListView refreshTable:_totalInfoArray]; 
  [sortDescriptor release]; 
  [sortDescriptors release];

NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"price" ascending:NO];//其中，price为数组中的对象的属性，这个针对数组中存放对象比较更简洁方便
  NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:&sortDescriptor count:1];
  [_totalInfoArray sortUsingDescriptors:sortDescriptors];
  [_airListView refreshTable:_totalInfoArray];
  [sortDescriptor release];
  [sortDescriptors release];

20120619更新

排序操作，NSArray提供了很多种方法，按照所利用的排序参数，可以简单分为descriptor,selector,function,和block排序。
数组排序的时候有sortedArrayUsingComparator方法，这里的参数为NSComparator,这个类其实是Block所定义的
typedef NSComparisonResult (^NSComparator)(id obj1,id obj2);
所以我们直接用NSComparator myComparator=^(id obj1,id obj2){};
Block其实可以看作JS里面的(){}();方法以及.Net中的匿名方法，即不需要声明就直接使用的方法，主要用处包括回调、事件处理和排序。声明和实现可以分开，也可以写在一起：
[plain] view plaincopyprint?NSInteger (^blockExample)(int,NSString*)=^(int i,NSString *s) 
{ 
       NSLog(@"%d,%@",i,s); 
}; 
blockExample(42,@"hello");

NSInteger (^blockExample)(int,NSString*)=^(int i,NSString *s)
{
       NSLog(@"%d,%@",i,s);
};
blockExample(42,@"hello");
对于NSArray排序或者其他需要Block作为参数的函数来说，可以写成下面两种形式:
//声明和使用

[plain]
NSComparison ( ^ageComparator )( id, id ) = ^( id o1, id o2 ) { 
    // 比较函数的实现 
}; 
    NSArray* objs_sortedByComparator = [objs sortedArrayUsingComparator:ageComparator]; 
// 不声明，彻底匿名使用 
    NSArray* objs_sortedByComparator = [objs sortedArrayUsingComparator:^( id o1, id o2 ) { //... 
    }];

NSComparison ( ^ageComparator )( id, id ) = ^( id o1, id o2 ) {
    // 比较函数的实现
};
    NSArray* objs_sortedByComparator = [objs sortedArrayUsingComparator:ageComparator];
// 不声明，彻底匿名使用
    NSArray* objs_sortedByComparator = [objs sortedArrayUsingComparator:^( id o1, id o2 ) { //...
    }];

例子：

[plain]
NSArray    *array = [NSArray arrayWithObjects:@"71", @"16", @"51", @"104", @"13",@"2",@"1", nil]; 
 
 
    array = [array sortedArrayUsingComparator:(NSComparator)^(id obj1, id obj2) { 
        return (arc4random() % 3) - 1; 
    }]; 
 
 
   // NSLog(@"array:%@", array); 
 
 
    NSArray *sortedArray = [array sortedArrayUsingComparator: ^(id obj1, id obj2) {  
 
 
        if ([obj1 integerValue] > [obj2 integerValue]) {  
            return (NSComparisonResult)NSOrderedAscending;  
        }  
 
 
        if ([obj1 integerValue] < [obj2 integerValue]) {  
            return (NSComparisonResult)NSOrderedDescending;  
        }  
        return (NSComparisonResult)NSOrderedSame;  
 
 
    }];  
 
 
 
 
sortedArray 是排好序的时间对象数组 
 
 
    // 按时间排序 
 
 
    NSArray *sortedArray = [srcArrary sortedArrayUsingComparator:^(id obj1, id obj2) 
 
 
                            { 
 
 
                                NSComparisonResult result = [obj1 compare:obj2]; 
 
 
                                switch(result) 
                                { 
                                    case NSOrderedAscending: 
                                        return NSOrderedDescending;             
                                    case NSOrderedDescending: 
                                        return NSOrderedAscending; 
                                    case NSOrderedSame: 
                                        return NSOrderedSame; 
                                    default: 
                                        return NSOrderedSame;   
                                } // 时间从近到远（远近相对当前时间而言） 
 
 
                            }];

NSArray    *array = [NSArray arrayWithObjects:@"71", @"16", @"51", @"104", @"13",@"2",@"1", nil];

array = [array sortedArrayUsingComparator:(NSComparator)^(id obj1, id obj2) {
        return (arc4random() % 3) - 1;
    }];

// NSLog(@"array:%@", array);

NSArray *sortedArray = [array sortedArrayUsingComparator: ^(id obj1, id obj2) {

if ([obj1 integerValue] > [obj2 integerValue]) {
            return (NSComparisonResult)NSOrderedAscending;
        }

if ([obj1 integerValue] < [obj2 integerValue]) {
            return (NSComparisonResult)NSOrderedDescending;
        }
        return (NSComparisonResult)NSOrderedSame;

}];

sortedArray 是排好序的时间对象数组

// 按时间排序

NSArray *sortedArray = [srcArrary sortedArrayUsingComparator:^(id obj1, id obj2)

{

NSComparisonResult result = [obj1 compare:obj2];

switch(result)
                                {
                                    case NSOrderedAscending:
                                        return NSOrderedDescending;           
                                    case NSOrderedDescending:
                                        return NSOrderedAscending;
                                    case NSOrderedSame:
                                        return NSOrderedSame;
                                    default:
                                        return NSOrderedSame; 
                                } // 时间从近到远（远近相对当前时间而言）

}];

//随机排序

[plain]
NSArray    *array = [NSArray arrayWithObjects:@"1", @"2", @"3", @"4", @"5", nil]; 
    array = [array sortedArrayUsingComparator:(NSComparator)^(id obj1, id obj2) { 
        return (arc4random() % 3) - 1; 
    }]; 
    NSLog(@"array:%@", array);

NSArray    *array = [NSArray arrayWithObjects:@"1", @"2", @"3", @"4", @"5", nil];
    array = [array sortedArrayUsingComparator:(NSComparator)^(id obj1, id obj2) {
        return (arc4random() % 3) - 1;
    }];
    NSLog(@"array:%@", array);