objective-c中获取时间的方法

－－－－－－头文件

#import <Foundation/Foundation.h>

#include <mach/mach_time.h>

@interfaceTimeStampHelper : NSObject

+ (NSTimeInterval)timestamp;

@end

－－－－实现文件

#import "TimeStamp.h"

@implementationTimeStampHelper

+ (NSTimeInterval)timestamp

{

    // get the timebase info -- different on phone and OSX

   mach_timebase_info_data_t info;

   mach_timebase_info(&info);

    

    // get the time

   uint64_tabsTime = mach_absolute_time();

    

    // apply the timebase info

   absTime *= info.numer;

    absTime /= info.denom;

    

    // convert nanoseconds into seconds and return

   return (NSTimeInterval) ((double) absTime / 1000000000.0);

}

@end