iOS開發(fā)中很少需要自己寫排序的算法，因?yàn)樘O果已經(jīng)為我們封裝好了。
簡(jiǎn)單的數(shù)值排序
NSMutableArray* arr = [NSMutableArrayarrayWithObjects:
[NSNumber numberWithInt:0],
[NSNumber numberWithInt:3],
[NSNumber numberWithInt:2],
[NSNumber numberWithInt:1],
[NSNumber numberWithInt:7],
[NSNumber numberWithInt:8],
[NSNumber numberWithInt:9],
[NSNumber numberWithInt:10],
[NSNumber numberWithInt:6],
[NSNumber numberWithInt:5],
[NSNumber numberWithInt:4],
nil];
// 升序
// 0 --> 10
[arr sortUsingComparator:^NSComparisonResult(__strongid obj1,__strong id obj2){
return [obj1 intValue] > [obj2intValue];
}];
// 降序
// 10 --> 0
[arr sortUsingComparator:^NSComparisonResult(__strongid obj1,__strong id obj2){
return [obj1 intValue] < [obj2intValue];
}];
復(fù)雜類型排序
NSMutableArray* arr = [NSMutableArray arrayWithObjects:@"C", @"A", @"H", @"I", @"B", @"D", @"J", @"E", @"F", @"G", @"K", nil];
// 升序
// A --> K
[arr sortUsingComparator:^NSComparisonResult(__strong id obj1,__strong id obj2){
NSString *str1=(NSString *)obj1;
NSString *str2=(NSString *)obj2;
return [str1 compare:str2];
}];
// 降序
// K --> A
[arr sortUsingComparator:^NSComparisonResult(__strong id obj1,__strong id obj2){
NSString *str1=(NSString *)obj1;
NSString *str2=(NSString *)obj2;
return [str2 compare:str1];
}];
