- (NSString *) convertImage: (UIImage *) image
{
    NSData *imageData = nil;
    NSString *mimeType = nil;
    
    if ([self imageHasAlpha: image]) {
        imageData = UIImagePNGRepresentation(image);
        mimeType =  pngType;
    } else {
        imageData = UIImageJPEGRepresentation(image, 1.0f);
        mimeType = jpgType;
    }
    
    return [NSString stringWithFormat: base64, mimeType,
            [imageData base64EncodedStringWithOptions: 0]];
    
}

- (BOOL) imageHasAlpha: (UIImage *) image
{
    CGImageAlphaInfo alpha = CGImageGetAlphaInfo(image.CGImage);
    return (alpha == kCGImageAlphaFirst ||
            alpha == kCGImageAlphaLast ||
            alpha == kCGImageAlphaPremultipliedFirst ||
            alpha == kCGImageAlphaPremultipliedLast);
}

• tip 服務(wù)端接收數(shù)據(jù)是， android和ios可能轉(zhuǎn)換的不一樣， 服務(wù)端如果不做處理需要, 此處代碼是weex代碼， js分離獲取base64字符串

  
  
  image.png