我有一个从javascript获取的数据URI，并尝试通过php保存。我使用以下代码给出了明显损坏的图像文件：

  $data = $_POST['logoImage'];

  $uri = substr($data,strpos($data,",")+1);

  file_put_contents($_POST['logoFilename'], base64_decode($uri));



data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAoAAAAKCAYAAACNMs 9AAAACXBIWXMAAAsTAAALEwEAmpwYAAAAxklEQVQYlYWQMW7CUBBE33yITYUUmwbOkBtEcgUlTa7COXIVV5RUkXKC5AxU EdyZVD4kyKxkwIrr9vd0c7Oih aopinLNsF6Qkg2XW4XJ7LGFsAAcTV6lF5/jLdbALA9XDAXYfthFQVx OrmqKYK88/7rbbMFksALieTnzu9wDYTj6f70PKsp2kwAiSvjXNcvkWpAfNZkzWa/5a9yT7fdoX7rrB7hYh2fXo9HdjPYQZu3MIU8bYIlW20y0RUlXG2Kpv/vfwLxhTaSQwWqwhAAAAAElFTkSuQmCC

代码下面是实际的图像，作为Data-URI。’logoImage’是上面的字符串，而$ uri是字符串减去’image / jpeg; base64，’。