//屏幕尺寸
CGRect rect = [[UIScreen mainScreen] bounds];
  CGSize size = rect.size;
  CGFloat width = size.width;
  CGFloat height = size.height;
  NSLog(@"print %f,%f",width,height);

//分辨率
CGFloat scale_screen = [UIScreen mainScreen].scale;
width*scale_screen,height*scale_screen

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
  [super viewDidLoad];
  
  
//  定义一个可变数组，用来存放所有字体
  NSMutableArray *fontarray = [NSMutableArray arrayWithCapacity:10];
//  遍历UI字体
  for (id x in [UIFont familyNames]) {
    NSLog(@"%@",x);
    [fontarray addObject:x];
  }
  
  
//  直接把字体存储到数组中
  NSArray *fontarrauy2 = [UIFont familyNames];
  NSLog(@"%@",fontarrauy2);
  
  
//  创建一个label，用来显示设定某种字体的字符串
  UILabel *mylab1 = [[UILabel alloc]initWithFrame:CGRectMake(100, 100, 200, 50)];
  mylab1.font = [UIFont systemFontOfSize:20];
  mylab1.font = [UIFont fontWithName:@"Zapfino" size:18];
  mylab1.font = [UIFont fontWithName:[fontarray objectAtIndex:10] size:18];
  mylab1.text = @"HelloWorld";
  [self.view addSubview:mylab1];
  
//  新建一个可变数组，用来存放使用for循环批量创建的label
  NSMutableArray *labarr = [NSMutableArray arrayWithCapacity:100];
  
  for (int x=0; x<24; x++) {
    for (int y=0; y<3; y++) {
//      循环创建72个label，每个label横向间距135-130=5，纵向间距30-28=2，
      UILabel *lab = [[UILabel alloc]initWithFrame:CGRectMake(y*135+7, x*30+20, 130, 28)];
      lab.backgroundColor = [UIColor colorWithRed:0.820 green:0.971 blue:1.000 alpha:1.000];
      lab.text = @"HelloWorld";
//      将创建好的label加入到可变数组
      [labarr addObject:lab];
    }
  }
  
//  使用for循环给72个label的字体设置各种字体格式
  for (int i=0; i<72; i++) {
    UILabel *lab = [labarr objectAtIndex:i];
    NSString *fontstring = [fontarray objectAtIndex:i];
    lab.font = [UIFont fontWithName:fontstring size:18];
    [self.view addSubview:[labarr objectAtIndex:i]];
  }
  
}

- (void)didReceiveMemoryWarning {
  [super didReceiveMemoryWarning];
  // Dispose of any resources that can be recreated.
}

@end