UIImage按比例縮放

縮放圖片比例

- (UIImage *)TelescopicImageToSize:(CGSize) size

{

    UIGraphicsBeginImageContext(size);

    [self drawInRect:CGRectMake(0, 0, size.width, size.height)];

    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    return newImage;

}