Question

我的服务器发送图片（base64）以及每个请求的时间戳，我只是将SDWebImage集成到我的应用程序中，我想知道如何访问SDWebImage从中获取的原始NSData

[imageView setImageWithURL:[NSURL URLWithString:[NSString stringWithFormat:@""]]];

这样我可以将文字与图像分开

Answer 1

您可以使用此方法

[UIImage sd_imageWithData:[NSData dataWithContentOfURL:[NSURL URLWithString:urlStr]];

Answer 2

您想将存储在NSData对象中的字节转换为UIImage对象，对吗？

UIImage *ImageFromBytes(NSData *data, CGSize targetSize)
{
    // Check data
    int width = targetSize.width;
    int height = targetSize.height;
    if (data.length < (width * height * 4))
    {
        NSLog(@"Error: Got %d bytes. Expected %d bytes",
            data.length, width * height * 4);
        return nil;
    }

    // Create a color space
    CGColorSpaceRef colorSpace =
        CGColorSpaceCreateDeviceRGB();
    if (colorSpace == NULL)
    {
        NSLog(@"Error creating RGB colorspace");
        return nil;
    }

    // Create the bitmap context
    Byte *bytes = (Byte *) data.bytes;
    CGContextRef context = CGBitmapContextCreate(
        bytes, width, height,
        BITS_PER_COMPONENT, // 8 bits per component
        width * ARGB_COUNT, // 4 bytes in ARGB
        colorSpace,
        (CGBitmapInfo) kCGImageAlphaPremultipliedFirst);
    CGColorSpaceRelease(colorSpace );
    if (context == NULL)
    {
        NSLog(@"Error. Could not create context");
        return nil;
    }

    // Convert to image
    CGImageRef imageRef = CGBitmapContextCreateImage(context);
    UIImage *image = [UIImage imageWithCGImage:imageRef];

    // Clean up
    CGContextRelease(context);
    CFRelease(imageRef);

    return image;
}

如果要跳过使用第三方实用程序在NSData对象中存储图像字节：

NSData *BytesFromRGBImage(UIImage *sourceImage)
{
    if (!sourceImage) return nil;

    // Establish color space
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
    if (colorSpace == NULL)
    {
        NSLog(@"Error creating RGB color space");
        return nil;
    }

    // Establish context
    int width = sourceImage.size.width;
    int height = sourceImage.size.height;
    CGContextRef context = CGBitmapContextCreate(
        NULL, width, height,
        8, // bits per byte
        width * 4, // bytes per row
        colorSpace,
        (CGBitmapInfo) kCGImageAlphaPremultipliedFirst);
    CGColorSpaceRelease(colorSpace);
    if (context == NULL)
    {
        NSLog(@"Error creating context");
        return nil;
    }

    // Draw source into context bytes
    CGRect rect = (CGRect){.size = sourceImage.size};
    CGContextDrawImage(context, rect, sourceImage.CGImage);

    // Create NSData from bytes
    NSData *data =
        [NSData dataWithBytes:CGBitmapContextGetData(context)
            length:(width * height * 4)]; // bytes per image
    CGContextRelease(context);
    return data;
}

访问使用SDWebImage下载的NSData

2 个答案: