iOS 判断一断代码的执行时间（从网上看的，自己实现一下）

//创建一个.h 文件

// Method.h

#ifndef NonAtomicTest_Method_h

#define NonAtomicTest_Method_h

#import <mach/mach_time.h>

//c函数实现 返回值类型 函数名 函数参数（是一个block）

CGFloat BNRTimeBlock (void (^block)(void)) {

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;

uint64_t nanos = elapsed * info.numer / info.denom;

return (CGFloat)nanos / NSEC_PER_SEC;

} // BNRTimeBlock

#endif

//直接使用

#import "ViewController.h"

#import "Method.h" //引用头文件即可调用 BNRTimeBlock

#define LOOPAGE 10000000

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {

[super viewDidLoad];

[self test];

}

-(void)test {

CGFloat time;

NSString *thing1 = @"hi";

NSString *thing2 = @"hello there";

//block 的实现

time = BNRTimeBlock(^{

for (int i = 0; i < LOOPAGE; i++) {

[thing1 isEqual: thing2];

}

});

NSLog (@"isEqual: time: %f\n", time);

time = BNRTimeBlock(^{

for (int i = 0; i < LOOPAGE; i++) {

[thing1 isEqualToString: thing2];

}

});

NSLog(@"isEqualToString: time: %f\n", time);

}

@end

控制台输出：

NonAtomicTest[3114:126739] isEqual: time: 0.279763

NonAtomicTest[3114:126739] isEqualToString: time: 0.275132