Get rid of the ZERO in a STRING

jacrewq

I have a $string = "021003249002......." or something like that. I'd like to get rid of the zero in front to make it just "210032...."

Please help

mahers


$mystring = "021003249002";

$mystring = substr($mystring, 1);

jacrewq

this code gives me error:

<?
$mystring_=_"asklfhdkjsafh";
$mystring_=_substr($mystring,1);
echo $mystring;
?>

Parse error: parse error, unexpected T_CONSTANT_ENCAPSED_STRING in /home/user/public_html/file.php on line 2

mahers

Thats because of those underscores before and after the "=" sign.

jacrewq

doh. how did they get there?

mahers

If you copy/paste from a html page displaying the code (like these forums) it also takes with it some hidden characters. I'm not exactly sure but if you want to avoid it you can save the html page as .txt then copy/paste from the .txt file.

mdj

Cool,

How would you write this so it only removes the first number if it is a 0.

mahers

With a simple if statement.

if($mystring{0} == "0") {
    $mystring = substr($mystring,1);
}

// Or

if(substr($mystring,0,1) == "0") {
    $mystring = substr($mystring,1);
}

Both should work.

majik-sheff

If your string is nothing but a number you can use the internal type conversion of PHP to your advantage.:

$myString = "003871768762439876234";
$myNumber = $myString + 0;
echo $myNumber;

will print:
3871768762439876234

intenz

Eek...

$string = '02313214';
if( $string[0] == '0' )
     $string = substr( $string, 1 );

majik-sheff

Of course, if you just want to strip 0s off of an arbitrary string, you can use regular expressions:

$myString = "000advnjhe13297y14";
preg_match("/^0*([^0].*$)/U", $myString, $matches);
echo $matches[1];

Will print:
advnjhe13297y14

This method is a bit opaque compared to itenz's method, but an order of magnitude faster for the engine.

ednark

use a different regular expression function... [man]preg_replace[/man] you can shorten the regex given by majik-sheff to just the begining of his

you want to find all leading 0's, and replace them with nothing

/^0*/

// just say anything between these is the regular expression

^ matches the begining of the string

0 matches... well 0

says match any number of the proceding thing including none, so it really means find any number of 0's

$string = preg_replace( '/^0*/', '', $string );

ednark

doh!!! i just remembered that the [man]trim[/man] function can be passed something arbitrary to trim off the string

[man]ltrim[/man] will remove any set of chatacters from the beginning of a string

$clean_string = ltrim( $dirty_string, '0' );

majik-sheff

touche, ednark, touche.

I think we've covered just about EVERY possible way to do this now. 🙂

Weedpacket

Originally posted by majik-sheff
I think we've covered just about EVERY possible way to do this now. 🙂

Oh, dangerous thing to say when I'm in earshot 😉

$clean_string = substr($dirty_string, strspn($dirty_string,'0'));

(This from a guy who used a sin() function to test if a number was even or odd.)

mdj

Thats Excellent Advice guys, Thanks very mutch!!!

Hopefully this post will help anyone who needs to edit their number strings in future.

Seeing as every possible sittuation seems to be covered!!

diego25

LoL! How do you test even or odd with the sin() function??

Diego

Weedpacket

Originally posted by diego25
LoL! How do you test even or odd with the sin() function??

Diego

$even = sin($i*M_PI+M_PI/2)>0;

To be honest, it was an analogue machine: the code above is a PHP translation of something I scribbled down at the time (the camshaft in question usually computed cos(), hence the π/2 term - the shaft was manually installed one quarter turn ahead).

diego25

Ahh, nice...makes sense....

Diego