ios创建二维码

#import "LCTwoCodeImage.h"

@implementation LCTwoCodeImage

+(UIImage *) GotoCreatMyTwoCode :(NSString *) string {

//通过传入的字符串来创建二维码初始图层渲染

CIImage * firstImage = [self creatCIImageFromString:string];

//通过 CIImage 来生成二维码

UIImage * qrCode = [self createNonInterpolatedUIImageFormCIImage:firstImage withSize:250.0f];

return qrCode;

}

+(UIImage *)createNonInterpolatedUIImageFormCIImage:(CIImage *)image withSize:(CGFloat) size {

CGRect extent = CGRectIntegral(image.extent);

CGFloat scale = MIN(size/CGRectGetWidth(extent), size/CGRectGetHeight(extent));

// create a bitmap image that we'll draw into a bitmap context at the desired size;

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:image fromRect:extent];

CGContextSetInterpolationQuality(bitmapRef, kCGInterpolationNone);

CGContextScaleCTM(bitmapRef, scale, scale);

CGContextDrawImage(bitmapRef, extent, bitmapImage);

// Create an image with the contents of our bitmap

CGImageRef scaledImage = CGBitmapContextCreateImage(bitmapRef);

// Cleanup

CGContextRelease(bitmapRef);

CGImageRelease(bitmapImage);

return [UIImage imageWithCGImage:scaledImage];

}

+(CIImage *)creatCIImageFromString:(NSString *) string {

NSData * stringData = [string dataUsingEncoding:NSUTF8StringEncoding];

//添加图层

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

[qrFiler setValue:stringData forKey:@"inputMessage"];

[qrFiler setValue:@"M" forKey:@"inputCorrectionLevel"];

return [qrFiler outputImage];

}

@end