CoreImage原生生成二维码(不使用第三方库)

1.首先要导入CoreImage.framework框架
2.引入<CoreImage/CoreImage.h>头文件

#import <CoreImage/CoreImage.h>

根据文本信息生成二维码

-(UIImage *)generateQRCodeWithInfo:(NSString *)info
{
    NSData *data = [info dataUsingEncoding:NSUTF8StringEncoding];
    //过滤器
    CIFilter *fiter =[CIFilter filterWithName:@"CIQRCodeGenerator"];
    //内容和纠错级别
    [fiter setValue:data forKey:@"inputMessage"];
    [fiter setValue:@"M" forKey:@"inputCorrectionLevel"];
    UIImage *image=[UIImage imageWithCIImage:fiter.outputImage];
    return image;
}

3.使用方法如下

- (void)viewDidLoad {
    [super viewDidLoad];
    UIImageView  *imv=[[UIImageView alloc]initWithFrame:CGRectMake(0, 0, 200, 200)];
    //生成二维码
    imv.image=[self generateQRCodeWithInfo:@"http://www.baidu.com"];
    [self.view addSubview:imv];
    imv.center=self.view.center;
}