CODEWITHSUNDEEP
phpuuidstring-matching
Quill Littlefeather
Quill Littlefeather

Reputation: 35

How do I extract a UUID from a string when the general format of the string is unknown?

I’m working on a PHP script in which the format one of the strings I’m getting as input is unknown. For example, I may get the input: 

user Name <7a240011-1b54-4a91-be27-a5cf8f474a39

Or I could get the input:

7a240011-1b54-4a91-be27-a5cf8f474a39

My issue if the string comes in like this:

user Name <7a240011-1b54-4a91-be27-a5cf8f474a39

How do I remove user Name < so all I’m left with is the UUID?

Now, what’s making this even harder is the UUID is never the same and user Name < will always have a different name.

Upvotes: 1

Views: 2019

Answers (3)

frymaster
frymaster

Reputation: 674

the easiest solution is that you can just strip off everything before the first ocurrence of '<'. i've substituted 'name' here with two different sample names to illustrate:

<?php

$name1 = "user Michael <7a240011-1b54-4a91-be27-a5cf8f474a39";
$name2 = "user Jasvinder <7a240011-1b54-4a91-be27-a5cf8f474a39";

print substr($name1, strpos($name1, "<")+1);
print substr($name2, strpos($name2, "<")+1);

note, though, that if the "Name" field contains "<", there will be difficulties.

edit now that you've accepted this as the solution, id' like to change it something better:

<?php

$name1 = "user Michael <7a240011-1b54-4a91-be27-a5cf8f474a39";
$name2 = "user Jasvinder <7a240011-1b54-4a91-be27-a5cf8f474a39";
$name3 = "7a240011-1b54-4a91-be27-a5cf8f474a39";

print preg_replace("/^.*\</","",$name1);
print preg_replace("/^.*\</","",$name2);
print preg_replace("/^.*\</","",$name3);

this handles both cases which the previous one, as was pointed out, didn't

Upvotes: 0

GolezTrol
GolezTrol

Reputation: 116110

You can easily do this with strpos and substr. strpos returns the index of a character or false if it is not found. That way, you can leave the string untouched if it doesn't contain an <.

Note that you need a strict comparison operator (=== or !==) when checking for false, because the string may contain a < in position 0.=, which would also evaluate to false (or vice versa) when compared using normal comparison operators (==, !=). 

<?php
$x = 'user Name <7a240011-1b54-4a91-be27-a5cf8f474a39';

// Find the position of the `<`.
$p = strpos($x, '<');

// If that character exists, copy only the part after it.   
if ($p !== false) {
  $x = substr($x, $p+1);
}

echo $x;

You can easily make a function out of this so you can call it from anywhere. And as you can see it handles cases for different user names, or just a code without a user name at all:

<?php
function getUserId($input) {
  $p = strpos($input, '<');

  if ($p !== false) {
    $input = substr($input, $p+1);
  }
  return $input;
}

echo getUserId('user Name <7a240011-1b54-4a91-be27-a5cf8f474a39') . '<br>';
echo getUserId('user Longer Name <7a240011-1b54-4a91-be27-a5cf8f474a39') . '<br>';
echo getUserId('7a240011-1b54-4a91-be27-a5cf8f474a39') . '<br>'a;

Upvotes: 0

icktoofay
icktoofay

Reputation: 129001

That seems like one of the few legitimate uses of regular expressions. After writing a regular expression to match UUIDs (like this one), you can throw your string into preg_match, and if there are any UUIDs in it, it will find them and you can extract them.

Upvotes: 1

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