iOS 通过字符串生成二维码图片的方法

最近写个项目正好遇到了要自己生成二维码图片,研究了一下写了下面通过字符串生成二维码图片的方法.大家可以拿过直接用的.

下面这个几个方法可以将字符串进行转换生成二维码图片.

直接调用这个下面这个:- (void)QRCodeMethod:(NSString *)qrCodeString 方法传入你想要转换的字符串即可.

/*  ============================================================  */
#pragma mark - 生成二维码的方法
- (void)QRCodeMethod:(NSString *)qrCodeString {

    UIImage *qrcodeImg = [self createNonInterpolatedUIImageFormCIImage:[self createQRForString:qrCodeString] withSize:250.0f];
    // ** 将生成的
    self.QRCodeView.image = qrcodeImg;
}

/*  ============================================================  */
#pragma mark - InterpolatedUIImage
- (UIImage *)createNonInterpolatedUIImageFormCIImage:(CIImage *)image withSize:(CGFloat) size {
    CGRect extent = CGRectIntegral(image.extent);
    CGFloat scale = MIN(size/CGRectGetWidth(extent), size/CGRectGetHeight(extent));
    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);
    
    CGImageRef scaledImage = CGBitmapContextCreateImage(bitmapRef);
    // Cleanup
    CGContextRelease(bitmapRef);
    CGImageRelease(bitmapImage);
    return [UIImage imageWithCGImage:scaledImage];
}

#pragma mark - QRCodeGenerator
- (CIImage *)createQRForString:(NSString *)qrString {
    
    NSData *stringData = [qrString dataUsingEncoding:NSUTF8StringEncoding];
    
    CIFilter *qrFilter = [CIFilter filterWithName:@"CIQRCodeGenerator"];
    
    [qrFilter setValue:stringData forKey:@"inputMessage"];
    [qrFilter setValue:@"M" forKey:@"inputCorrectionLevel"];

    return qrFilter.outputImage;
}

#pragma mark - imageToTransparent
void ProviderReleaseData (void *info, const void *data, size_t size){
    free((void*)data);
}
- (UIImage*)imageBlackToTransparent:(UIImage*)image withRed:(CGFloat)red andGreen:(CGFloat)green andBlue:(CGFloat)blue{
    const int imageWidth = image.size.width;
    const int imageHeight = image.size.height;
    size_t      bytesPerRow = imageWidth * 4;
    uint32_t* rgbImageBuf = (uint32_t*)malloc(bytesPerRow * imageHeight);
    
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
    CGContextRef context = CGBitmapContextCreate(rgbImageBuf, imageWidth, imageHeight, 8, bytesPerRow, colorSpace, kCGBitmapByteOrder32Little | kCGImageAlphaNoneSkipLast);
    CGContextDrawImage(context, CGRectMake(0, 0, imageWidth, imageHeight), image.CGImage);
    
    int pixelNum = imageWidth * imageHeight;
    uint32_t* pCurPtr = rgbImageBuf;
    for (int i = 0; i < pixelNum; i++, pCurPtr++){
        if ((*pCurPtr & 0xFFFFFF00) < 0x99999900){
            
            uint8_t* ptr = (uint8_t*)pCurPtr;
            ptr[3] = red; //0~255
            ptr[2] = green;
            ptr[1] = blue;
        }else{
            uint8_t* ptr = (uint8_t*)pCurPtr;
            ptr[0] = 0;
        }
    }
    
    CGDataProviderRef dataProvider = CGDataProviderCreateWithData(NULL, rgbImageBuf, bytesPerRow * imageHeight, ProviderReleaseData);
    CGImageRef imageRef = CGImageCreate(imageWidth, imageHeight, 8, 32, bytesPerRow, colorSpace, kCGImageAlphaLast | kCGBitmapByteOrder32Little, dataProvider, NULL, true, kCGRenderingIntentDefault);
    CGDataProviderRelease(dataProvider);
    UIImage* resultUIImage = [UIImage imageWithCGImage:imageRef];
    
    CGImageRelease(imageRef);
    CGContextRelease(context);
    CGColorSpaceRelease(colorSpace);
    return resultUIImage;
}

以上就是将字符串转换成二维码图片的方法,大家可以拿过去直接用.只要调用第一个方法即可.

~~~~~~~~~~~~~~~~~~~~~~~~

最后编辑于
©著作权归作者所有,转载或内容合作请联系作者
平台声明:文章内容(如有图片或视频亦包括在内)由作者上传并发布,文章内容仅代表作者本人观点,简书系信息发布平台,仅提供信息存储服务。

推荐阅读更多精彩内容