检测代码执行时间的方法

整理了两种iOS中获取一个方法执行时间的方法，不多说，直接上代码
方法一
需要导入头文件 #import

CGFloat duration_time_block (void (^block) ()) {
    mach_timebase_info_data_t info;
    if (mach_timebase_info(&info) != KERN_SUCCESS) return -1.0;
    
    uint64_t start = mach_absolute_time();
    block();
    uint64_t end = mach_absolute_time();
    uint64_t elapsed = end - start;
    
    int64_t nanos = elapsed * info.numer / info.denom;
    return (CGFloat)nanos / NSEC_PER_SEC;
}

方法二

CGFloat clock_time_block (void (^block) ()){
    time_t time1 = clock();
    block();
    time_t time2 = clock();
    return ((CGFloat)(time2 - time1)) / CLOCKS_PER_SEC;
}