filter similar letters

[codrgii]

how can i check to see if a poster has posted similar words when posting something?

i want to stop them posting something like "hhhhh" or "aaaaa" and so on, how in php can that be done?

[Fadion]

You can do a simple search:

<?php
$banned_words = array('hhhhh', 'aaaaa');
foreach ($banned_words as $word) {
if (strpos($word, $text)) {
	 echo "$word is not allowed! Don't asked me why!";
}
}
?>

 

or replace those words directly:

<?php
$search = array('hhhhh', 'aaaaa');
$replace = '';

$text = str_replace($search, $replace, $text);
?>

 

EDIT: Now I'm seeing I totally misunderstood your question. Sorry.

[Psycho]

Are you looking for similar words OR words with repeated letters? When trying to filter user input you must be VERY specific as to your requirements.

[codrgii]

Are you looking for similar words OR words with repeated letters?

 

Basically i would like to filter out any junk posts with the same words in sequence more than 4 times, and if found then cancel/end the script.

[xyph]

Use regex, I suppose

 

This will match when someone repeats a single character 4 or more times in a row. Unicode-safe

$expr = '/(\X)\1{3,}+/u';

 

The same word/character etc is below

$expr = '/(\X+?)\1{3,}+/u';

 

These expressions are extremely slow, especially the second one. Tons of backtracking.