PHP file extension _ PHP Tutorial

How does PHP obtain the file extension. How to obtain the file extension in PHP is often used at work. here I will summarize the following methods. (Welcome to criticize and correct) method 1 functiongetF PHP how to obtain the file extension

During work, you often encounter file extensions. here I will summarize the following methods. (Welcome to criticize and correct)

Method 1

　　

Function getFileExtend_1 ($ fileName ){

$ Retval = "";

$ Pt = strtpos ($ fileName ,".");

If ($ pt ){

$ Retval = substr ($ fileName, $ pt + 1, strlen ($ fileName)-$ pt );

}

If ($ retval! = ""){

Return $ retval;

}

Return false;

}

?>

Method 2

　　

Function getFileExtend_2 ($ fileName ){

$ Extend = pathinfo ($ fileName );

$ Extend = strtolower ($ extend ['extension']);

If (is_string ($ extend )){

Return $ extend;

}

Return false;

}

?>

Method 3

　　

Function getFileExtend_3 ($ fileName ){

$ Extend = explode (".", $ fileName );

$ Va = count ($ extend)-1;

$ Extend = $ extend [$ va];

If (is_string ($ extend )){

Return $ extend;

}

Return false;

}

?>

In my work, users often encounter file extensions. here I will summarize the following methods. (Welcome to criticize and correct) Method 1: function getF...