[RESOLVED] ereg_replace question

dmacman1962

Hi everyone,

I believe this is the correct way to replace this value, but it is not working for me.

I have the following I want to remove ...

{2}-1

So I wrote

$link = ereg_replace("/{2/}/-1", "", $start);

but I get this error "Warning: ereg_replace() [function.ereg-replace]: REG_BADBR."

If I try it like this...

$link = ereg_replace("{2}-1", "", $start);

I don't get an error, but it will not strip out the text.

I know its a matter of escaping it out, I am just not understanding the correct procedure in this case.

Thanks in advance,

Don

troybtj

both '{' and '}' are regular expression characters (used to define repeats, etc), so you need to escape them.

<?php
//code here....

$link = ereg_replace("\{2\}-1", "", $start); 


// rest of code..
?>

laserlight

Incidentally, consider the use of the PCRE functions instead. In this case, use [man]preg_replace/man.

Actually, since you want to replace '{2}-1' with '', do not use regex at all. Use [man]str_replace/man.

dmacman1962

Thanks,

The str_replace did it.

I saw an earlier post of yours and you suggested the PCRE path, but I will be honest with you. I read the page and could not follow one single example on the page.

I would love to use it especially since you rate it so highly, but could you give an understandable example. Their page seems to be mostly an explanation of different variants and not real world examples like the other php.net pages.

Thanks,
Don

laserlight

In this case, if we modify troybtj's example to work with preg_replace(), it would just be a case of introducing pattern delimiters:

<?php
//code here....

$link = preg_replace('/\{2\}-1/', '', $start);

// rest of code..
?>

Much of the syntax is rather similiar (as in the case across many common regex libraries in use), but the difference in terms of best practice is because the ereg versions are getting phased out. This is attributed to the PCRE versions being faster, though I have not tested this myself.

dmacman1962

That makes more sense.

Basically, the entire string is enclosed in // and the special characters are escaped out .

Thanks, that kind of answer helps verses, those where people try to show off how complex they can make an example, and therefore completely lose the audience they were attempting to teach.

You have a knack of 'not' doing that. Well done!

Thanks!

Don

PS. and thanks to you troybtj's also!