This article mainly introduces the PHP string to obtain the file extension. Interested friends can refer to it. I hope it will be helpful to everyone.
The code is as follows:
$filename="123.jpg"; //方法一: function get_ext($file_name){ return array_pop(explode('.', $file_name)); //用.号对字符串进行分组 } echo get_ext($filename); //方法二: $fileEx=strtolower(substr(strrchr($filename,"."),1)); echo $fileEx; //方法三: $extend=pathinfo($filename); echo $extend['extension']; //方法四: $filetype=array("image/gif","image/jpeg"); //判断文件扩展名类型是否在该 数组中 if(in_array($_FILES['file']['type'],$filetype)){ //针对上传文件判断 echo $_FILES['file']['type']; }
Summary: The above is the entire content of this article, I hope it will be helpful to everyone's study.
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