[SOLVED] php command to detect numbers vs letters?

[Dimwhit]

I'm not sure how to word this well enough to even perform a search, but here's what I want to do:

 

I have a field whose value is a filename. I want to look at that name and return one set of code if the name starts with a letter (a-z) and another if it's a number (1-9).

 

Something like:

 

if ($filename starts with letter) {
echo "code 1";
} else if ($filename starts with number) {
echo "code 2";
}

 

I just don't know how, or if, that's doable. Is there something boneheadedly simple I'm don't know about?

[discomatt]

I'd use this

 

<pre><?php

$str = '123abc';

if(  ctype_digit( substr($str, 0, 1) ) === TRUE  ) {
echo 'Starts with a number';
} else {
echo 'Starts with a non-number';
}

?></pre>

[thebadbad]

You can access the first character with $filename[0], and then use ctype_alpha() and ctype_digit() to check for alphabetic or numeric chars (0-9).

 

<?php
$filename = 'alpha';
if (ctype_alpha($filename[0])) {
//first char alphabetic
} elseif (ctype_digit($filename[0])) {
//first char numeric
}
?>

[Dimwhit]

OK, I'm not having luck with either these. Let me start with the first one.

 

I'm assuming that in the following:

$str = "123abc";

I need to plug in my variable for '123abc', so it would look something like:

 

$str = "$filename";

Right? That should get the actual filename text (or numbers) for the script to work with. I keep getting the 'unexpected T_Variable error on that line (in both examples) every time.

 

Thanks for the help.

[Dimwhit]

I'm obviously missing something (and given that I'm still learning my way through php, that's not surpnising). But this is the entirety of the php code I'm working with:

 

<?php

$searchcriteria = array();
$searchcriteriausingquotes = array(('file'));

if (array_key_exists('file', $_GET)) {
    $file = $_GET['file'];
    if (strlen($file)) $searchcriteria['file'] = $file;
}

$str = $file;

if (ctype_digit($str[0]) === TRUE ) {
echo 'Starts with a number';
} else {
echo 'Starts with a non-number';
}

?>

 

I tried a hybrid of the two suggestions above, but I'm getting an 'unexpected T_String' error on the following line:

 

if (ctype_digit($str[0]) === TRUE ) {

 

Any thoughts on why?

 

 

[Dimwhit]

OK, Got it to work. I had to use thebadbad's suggested, because the other one wasn't working. But I had some bad invisible characters that were causing the problem.

 

Thanks for the help!