您将必须使用服务器上的路径来删除图像，而不是url.

You'll have to use the path on your server to delete the image, not the url.

unlink('/var/www/test/folder/images/image_name.jpeg'); // correct

您应该在unlink()之前删除@，在这种情况下，您会看到错误消息，提示找不到文件"或类似的内容.

you should remove the @ before unlink(), in that case you would have seen the error-message saying "file not found" or something like that.