Validate Username

[harchew]

How do I validate an user name in such a way that, it must contain at least an alpha and number. Only alpha,number and ._ are allow for the user name otherwise return invalid.

[uniflare]

you would use regular expresions, i believe there is another forum specifically for these questions:

http://www.phpfreaks.com/forums/index.php/board,43.0.html

----

im not so good with regex in php but you could do:

<?php

$string = "USER._NAME23";	// ex valid username

if(preg_match("/[^a-zA-Z0-9\._]/i",$string) == 0){
// valid characters
if(preg_match("/[0-9]/i",$string) == 0){
	// No Numbers Found
	echo("Username must contain at least 1 number");
}
if(preg_match("/[a-z]/i",$string) == 0){
	// No Letters Found
	echo("Username must contain at least 1 character");
}
$strlen = strlen($string);
if($strlen < 8 && $strlen > 16){
	echo("Username must be between 8 and 16 characters in length");
}
}else{
echo("You have illegal characters in your username, Legal characters include: A-Z, 0-9, a period (.), and an underscore ( _ )");
}

?>

 

hope this helps,

[harchew]

Its working perfectly. Thank you so much (Bow...)