preg_match and ereg

Hi,

I tried the following two functions to check if a variable is numeric or not. The first function gave me a negative result.

<?php

$myvar = 123;
if(!ereg("^[\d]*\.?\d*$",$myvar))
echo  "Amount Should be Numeric.";
else
echo "Amount is numeric";
?>

PHP:

But the second function worked.

<?php
$myvar = 123;
if(!preg_match("/^[\d]*\.?\d*$/",$myvar))
echo "Amount Should be Numeric.";
else
echo "Amount is numeric";
?>

PHP:

I could not understand the mystery behind it.

Can you explain plz?


Thanx

 

ereg uses POSIX.2 regular expressions syntax, so there is no "\d" there. Use "[[:digit:]]" insted of "\d"
So, this is correct code:

if(!ereg("^[[:digit:]]*\.?[[:digit:]]*$",$myvar))

PHP:

 

k thanx for the info.

 

or... you can use this

if (is_numeric($test)) {
echo "this variable is numeric
}

PHP: