文件上传 - php上传图片能直接用文件后缀判断类型吗？为什么，给个详细例子
php上传图片能直接用文件后缀判断类型吗？为什么，给个详细例子
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php上传图片能直接用文件后缀判断类型吗？为什么，给个详细例子
你愿意的话是可以的，传文件各种判断类型的方法中，文件头>MINE-Type>文件名后缀，但是没有一种是绝对安全的。想清楚如果有人有意无意犯错传了后缀名不对的文件，上传了可执行文件的情况该怎么办。
不能，因为你可以把非图片的后缀名改成 .jpg。
不可以，因为后缀你可以自定义的。据 @卖掉内裤去上网 说用 getimagesize() 判断类型很不错。
最好不要，这样子不安全。
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