highlight sequentially different word in PHP

Question

I want to highlight sequentially different between 2 string word in PHP, suppose I have 2 String like below.

$string1 = "TO THE ORDER OF United Bank Limited Arab -09254 DT:17-06-20212 ADS";
$string2 = "Arab TO THE ORDER OF United Bank Limited Arab TO -092541 KDS DT:17-06-20212";

The highlighted words should be Arab To -092541 and KDS. so far I have tried the below code.

<?php
function compare_strings($array1, $array2) {
$array1 = explode(" ", $array1);
$array2 = explode(" ", $array2);
$arSize1=count($array1);
$arSize2=count($array2);
$index=0;
  if($arSize1<$arSize2){
    for($i=0;$i<$arSize1;$i++){
      if($array1[$i]==$array2[($i+$index)]){
          echo ' '.$array1[$i];
      }
      else{
          echo ' <b>'.$array2[($i+$index)].'</b>'; 
          $index++;
          $i--;
      }
    }

  }
}
$string1 = "TO THE ORDER OF United Bank Limited Arab -09254 DT:17-06-20212 ADS";
$string2 = "Arab TO THE ORDER OF United Bank Limited Arab TO -092541 KDS DT:17-06-20212";
echo $string1.'<br/>';
compare_strings($string1,$string2);
?>

this code works fine if I only add words, like Arab To and KDS and don't change existing word -092541. when I change -09254 to -092541 it's start a infinite loop and shows Undefined array key error.

Expected highlighted words are Arab TO -092541 KDS

I tried below answers/libraries but none of these worked for my situation.

@Arif 's answer for a similar question
Side-by-side
class.Diff.php

Any help/guidance will be very appreciated.

If there is a pattern, are you consider use regex to achieve this? — Ali Briceño, Oct 21 '21 at 16:55
@AliBriceño yes if it is possible using regex I'll be happy to use. BTW as of now I got my desired output, please have look at answers. — Mahmood Sanjrani, Oct 22 '21 at 05:19

Shlomtzion · Answer 1 · 2021-10-21T08:12:33.560

0

You code is overly complicated ... and that's why you go to infinite loops...

Here is a suggestion with foreach loop, you don't need to care how long you arrays are in this example, since you are checking if the words that come from the array you are looping through appear in the other... so you are already checking all of the words in the array.

This means that if you use something like in_array() you will know if that word appear in the other array or not.

So here is a small change to your code:

<?php
function show_unique_strings($array1, $array2) {

    $array1 = explode(" ", $array1);
    $array2 = explode(" ", $array2);


    foreach ($array2 as $a2Val){

        $nKey = in_array($a2Val,$array1);
        if($nKey > 0){
            echo "<b> $a2Val </b>";
        } else {
            echo " $a2Val";
        }

    }

}

$string1 = "TO THE ORDER OF United Bank Limited Arab -09254 DT:17-06-20212 ADS";
$string2 = "Arab TO THE ORDER OF United Bank Limited Arab TO -092541 KDS DT:17-06-20212";
echo $string1.'<br/>';
show_unique_strings($string1,$string2);
?>

Will output:

TO THE ORDER OF United Bank Limited Arab -09254 DT:17-06-20212 ADS

Arab TO THE ORDER OF United Bank Limited Arab TO -092541 KDS DT:17-06-20212

This way we don't care if we run only on the 2nd array because for each word we do the check and echo one or the other... no need of counts and following our keys at all...:)

edited Oct 21 '21 at 08:12

answered Oct 21 '21 at 07:51

Shlomtzion

674
5
12

thanks for response, I ran your code but it is not giving expected out. I have edited my question and added expected output. – Mahmood Sanjrani Oct 21 '21 at 08:11
Oh, I understood the question wrong... I'll re-look at this! :) – Shlomtzion Oct 21 '21 at 08:18
Thank you so much, let me know if I didn't explain clearly. – Mahmood Sanjrani Oct 21 '21 at 08:32
Once you add words in the middle of the sentence everything breaks... There needs to be a rule system to this... – Shlomtzion Oct 21 '21 at 10:01
I don't get your point, are you saying that we have to limit user to add words in middle of sentence?? – Mahmood Sanjrani Oct 21 '21 at 10:12
There is no visible order here for the data given in the strings on the first the string the -09254 appears and after it the DT:17 and in the second string the -092541 appears and than KDS and than only the date... is there a format for these? – Shlomtzion Oct 21 '21 at 10:19
Let us [continue this discussion in chat](https://chat.stackoverflow.com/rooms/238389/discussion-between-mahmood-sanjrani-and-shlomtzion). – Mahmood Sanjrani Oct 21 '21 at 10:30

score 0 · Accepted Answer · answered Oct 21 '21 at 13:27

simplediff library did my job, I just had to modify code to meet my requirement.

<?php
function diff($old, $new){
    $matrix = array();
    $maxlen = 0;
    foreach($old as $oindex => $ovalue){
        $nkeys = array_keys($new, $ovalue);
        foreach($nkeys as $nindex){
            $matrix[$oindex][$nindex] = isset($matrix[$oindex - 1][$nindex - 1]) ?
                $matrix[$oindex - 1][$nindex - 1] + 1 : 1;
            if($matrix[$oindex][$nindex] > $maxlen){
                $maxlen = $matrix[$oindex][$nindex];
                $omax = $oindex + 1 - $maxlen;
                $nmax = $nindex + 1 - $maxlen;
            }
        }   
    }
    if($maxlen == 0) return array(array('d'=>$old, 'i'=>$new));
    return array_merge(
        diff(array_slice($old, 0, $omax), array_slice($new, 0, $nmax)),
        array_slice($new, $nmax, $maxlen),
        diff(array_slice($old, $omax + $maxlen), array_slice($new, $nmax + $maxlen)));
}

$string1 = "TO THE ORDER OF United Bank Limited Arab -09254 DT:17-06-20212 ADS";
$string2 = "Arab TO THE ORDER OF United Bank Limited Arab TO -092541 KDS DT:17-06-20212";
$arr=diff(explode(" ",$string1),explode(" ",$string2));
echo $string1.'<br/>';
$ret = '';
foreach($arr as $k){
        if(is_array($k)){
            $ret .= (!empty($k['i'])?"<b>".implode(' ',$k['i'])."</b> ":'');
        }
        else {
          $ret .= $k . ' ';
        }
    }
echo $ret;
?>

output:

TO THE ORDER OF United Bank Limited Arab -09254 DT:17-06-20212 ADS
Arab TO THE ORDER OF United Bank Limited Arab TO -092541 KDS DT:17-06-20212

highlight sequentially different word in PHP

2 Answers2