automatic convert word to link in PHP - php

Question

I want write a simple code that convert special words to special link (for wiki plugin), if it's not a link!
For example suppose we have a text "Hello! How are you?!" and
we want convert are to are, but if we have Hello! How are you?! or Hello! How are you?! does not change. Because it's a link.
How can I do it in PHP?! With preg_replace?! How to?
Thanks.

Answer 1

It's easy.
<?php
$string = "Hello! How are you?!";
$stringTwo = "Hello! how are you?!";
function turnTheWordIntoALink($string, $word, $link) {
if(isLink($string)) {
return $string;
} else {
$string = str_replace($word, "" . $word . "", $string);
return $string;
}
}
function isLink($string) {
return preg_match("/(<a href=\".\">)/", $string);
}
echo turnTheWordIntoALink($string, 'are', 'http://google.com');
echo turnTheWordIntoALink($stringTwo, 'are', 'http://google.com');
Output:
First function output: Hello! How are you?!
Second function output: Hello! how are you?!
Alternative:
If you want to not detect <a> tags which were closed, you can use this alternative code:
$stringThree = "Hello! how <a href=\"#\">are you?!";
function turnTheWordIntoALink($string, $word, $link) {
if(isLink($string)) {
return $string;
} else {
$string = str_replace($word, "" . $word . "", $string);
return $string;
}
}
function isLink($string) {
return preg_match("/(<a href=\".\">)+(.)+(<\/a>)/", $string);
}
echo turnTheWordIntoALink($stringThree, 'are', 'http://google.com') . "\n";
This gives the output: Hello! how <a href="http://google.com">are you?!

Answer 2

this code is about : if there is a some URL in some phrase it will convert to a link
$word = 'hello how are you google.com, wish you good time';
$prg = "/[a-zA-Z0-9\-\.]+\.[a-zA-Z]{2,3}(\/\S*)?/";
if(preg_match($prg, $word, $url))
{
echo preg_replace($prg, "<a href=http://$url[0]>{$url[0]}</a>", $word);
}
else
{
echo $word;
}

Answer 3

To better clarify the issue:
I have a HTML code that have some tags. I want some words in that, converted to some links. But if it is a another link does not convert. See below advanced example for special word you that we want linked to the google:
This is a sample text.
Hello?! How are you?!
Are you ready?!
should be convert to:
This is a sample text.
Hello?! How are you?!
Are you ready ?!
Note that the first you changed, but that second you was not changed, because it's in the another <a> tag.
Answer:
Because of this work has issue with regular expression, this problem can solve without regular expression. Here a simple solution is given:
$data = 'Hello! This is a sample text. <br/>'.
'Hello! This is a sample text. <br/>'.
'Hello! This is a sample text. <br/>'.
'Hello! This is a sample text. <br/>'.
'Hello! This is a sample text.';
$from = " is ";
$to = '<a href="http://www.google.com" > '.$from.' </a>';
echo $data;
$data = explode($from, $data);
echo "<br><br>";
echo $data[0];
$diff = 0;
for($i=1; $i<count($data); $i++){
$n = substr_count($data[$i-1], '<a ') + substr_count($data[$i-1], '<A ');
$m = substr_count($data[$i-1], '</a>') + substr_count($data[$i-1], '</A>');
$diff += $n-$m;
if($diff==0)
echo $to.$data[$i];
else
echo $from.$data[$i];
}