ios中通过代码生成二维码

话不多说，直接上代码

/**

 * 根据CIImage生成指定大小的UIImage

 *

 * @param image CIImage

 * @param size 图片宽度

 */

- (UIImage*)createNonInterpolatedUIImageFormCIImage:(CIImage*)image withSize:(CGFloat) size

{

    CGRect extent = CGRectIntegral(image.extent);

    CGFloatscale =MIN(size/CGRectGetWidth(extent), size/CGRectGetHeight(extent));

    // 1.创建bitmap;

    size_twidth =CGRectGetWidth(extent) * scale;

    size_theight =CGRectGetHeight(extent) * scale;

    CGColorSpaceRef cs = CGColorSpaceCreateDeviceGray();

    CGContextRef bitmapRef = CGBitmapContextCreate(nil, width, height, 8, 0, cs, (CGBitmapInfo)kCGImageAlphaNone);

    CIContext *context = [CIContext contextWithOptions:nil];

    CGImageRefbitmapImage = [contextcreateCGImage:imagefromRect:extent];

    CGContextSetInterpolationQuality(bitmapRef, kCGInterpolationNone);

    CGContextScaleCTM(bitmapRef, scale, scale);

    CGContextDrawImage(bitmapRef, extent, bitmapImage);

    // 2.保存bitmap到图片

    CGImageRef scaledImage = CGBitmapContextCreateImage(bitmapRef);

    CGContextRelease(bitmapRef);

    CGImageRelease(bitmapImage);

    return [UIImage imageWithCGImage:scaledImage];

}

调用以上方法

// 1. 实例化二维码滤镜

    CIFilter *filter = [CIFilter filterWithName:@"CIQRCodeGenerator"];

    // 2. 恢复滤镜的默认属性

    [filtersetDefaults];

    // 3. 将字符串转换成NSData

    NSString *urlStr = @"http://www.ychpay.com/down.html";//测试二维码地址,次二维码不能支付,需要配合服务器来二维码的地址(跟后台人员配合)

    NSData *data = [urlStr dataUsingEncoding:NSUTF8StringEncoding];

    // 4. 通过KVO设置滤镜inputMessage数据

    [filtersetValue:dataforKey:@"inputMessage"];

    // 5. 获得滤镜输出的图像

    CIImage*outputImage = [filteroutputImage];

    // 6. 将CIImage转换成UIImage，并放大显示 (此时获取到的二维码比较模糊,所以需要用下面的createNonInterpolatedUIImageFormCIImage方法重绘二维码)

    //    UIImage *codeImage = [UIImage imageWithCIImage:outputImage scale:1.0 orientation:UIImageOrientationUp];

    UIImageView *wechatImageView = [[UIImageView alloc] initWithFrame:CGRectMake(40, 30, SCREEN_WIDTH - 80, SCREEN_WIDTH - 80)];

    wechatImageView.image = [self createNonInterpolatedUIImageFormCIImage:outputImage withSize:200];//重绘二维码,使其显示清晰

    [self.viewaddSubview:wechatImageView];

只要将url替换成自己的url就好了