生成二维码
//根据字符串生成二维码图片
- (UIImage *)createQRForString:(NSString *)qrString {
NSData *stringData = [qrString dataUsingEncoding:NSUTF8StringEncoding];
// 创建filter
CIFilter *qrFilter = [CIFilter filterWithName:@"CIQRCodeGenerator"];
// 设置内容和纠错级别
[qrFilter setValue:stringData forKey:@"inputMessage"];
[qrFilter setValue:@"M" forKey:@"inputCorrectionLevel"];
// CIImage
CIImage *qrCIImage = qrFilter.outputImage;
CGRect extent = CGRectIntegral(qrCIImage.extent);
CGFloat scale = 200;
// 创建bitmap;
size_t width = CGRectGetWidth(extent) * scale;
size_t height = CGRectGetHeight(extent) * scale;
CGColorSpaceRef cs = CGColorSpaceCreateDeviceGray();
CGContextRef bitmapRef = CGBitmapContextCreate(nil, width, height, 8, 0, cs, (CGBitmapInfo)kCGImageAlphaNone);
CIContext *context = [CIContext contextWithOptions:nil];
CGImageRef bitmapImage = [context createCGImage:qrCIImage fromRect:extent];
CGContextSetInterpolationQuality(bitmapRef, kCGInterpolationNone);
CGContextScaleCTM(bitmapRef, scale, scale);
CGContextDrawImage(bitmapRef, extent, bitmapImage);
// 保存bitmap到图片
CGImageRef scaledImage = CGBitmapContextCreateImage(bitmapRef);
CGContextRelease(bitmapRef);
CGImageRelease(bitmapImage);
return [UIImage imageWithCGImage:scaledImage];
}
生成的二维码为黑色带白色背景如果需要修改背景颜色参考--->原文地址