php – 如何检查文件是否是图像？

我可以检查某个文件是否是图像？在 PHP中怎么做？

如果文件不是图像,我想给出一个警报消息.

除了 getimagesize(),您可以使用 exif_imagetype()

exif_imagetype() reads the first bytes of an image and checks its signature.

When a correct signature is found,the appropriate constant value will be returned otherwise the return value is FALSE. The return value is the same value that getimagesize() returns in index 2 but exif_imagetype() is much faster.

对于这两个函数,如果文件未被确定为图像,则返回FALSE.

原文地址：https://www.jb51.cc/php/131901.html