PHP Replace Between Tags - php

Question

I am looking for a quick way to replace text in a string that is between two tags.
The string contains <!-- Model # Start --> <!-- Model # End --> Tags.
I just want to replace what is between the tags, I believe preg_replace() will do this but I am not sure how to make it work.

Answer 1

To use preg_replace, pass in the original string and a regular expression - the matching result will be returned. There is not much more to say about that method as you need to understand regular expressions to use it.
Here is a programatic solution, possibly not the most efficient code, but gives you an indication of what it is doing.
$tagOne = "[";
$tagTwo = "]";
$replacement = "Greg";
$text = "Hello, my name is [NAME]";
$startTagPos = strrpos($text, $tagOne);
$endTagPos = strrpos($text, $tagTwo);
$tagLength = $endTagPos - $startTagPos + 1;
$text = substr_replace($text, $replacement, $startTagPos, $tagLength);
echo $text;
Outputs: Hello, my name is Greg.

Answer 2

$tagOne = "[";
$tagTwo = "]";
$replacement = "Greg";
$text = "Hello, my name is [NAME] endie ho [NAME] \n [NAME]";
$textLength = strlen($text);
for ($i; $i< $textLength; $i++) {
$startTagPos = strrpos($text, $tagOne);
$endTagPos = strrpos($text, $tagTwo);
$tagLength = $endTagPos - $startTagPos + 1;
if ($startTagPos<>0) $text = substr_replace($text, $replacement, $startTagPos, $tagLength);
}
echo $text;
Please note, the if statement that checks if there is a tag pos left, otherwise, for all the textlength - # of tags, your start position of 0, in this case 'H', will get gregs :)
The above outputs
Hello, my name is Greg endie ho Greg Greg