您的代码与您提供的示例数据一起按预期工作:

Your code does work as expected with the example data you gave:

NSArray *_timesArray = @[@1, @23, @57, @59, @120];
NSTimeInterval currentTime = 109;
NSInteger playerTime=currentTime;
NSUInteger index = [_timesArray indexOfObject:@(playerTime)
                                inSortedRange:NSMakeRange(0, _timesArray.count-1)
                                      options:NSBinarySearchingFirstEqual | NSBinarySearchingInsertionIndex
                              usingComparator:^(id a, id b) {
                                  return [a compare:b];
                              }];
NSLog(@"Index: %lu", (unsigned long)index);

输出:

Index: 4

检查您的输入.很可能它们不是您认为的那样.

Check your inputs. Likely they are not what you think they are.