str_replace for exact match

Quote: Originally Posted by pankajit09 Hello, Code: ( text ) $x = "tyu"   $y="3"   $eq = "asa+tyu-tyut+1"   $result = str_replace($x,$y,$eq);   echo $result; $result has "asa+3-3t+1" I expect "asa+3-tyut+1" Please help .

That's pretty difficult to do, if not impossible unless you find some other pattern in your string.

use preg_replace() http://us2.php.net/preg_replace

to implent some kind of pattern...

for example

does it always end with t, those that end with "t" do not replace?

does it have to end with "-" everytime?

should it end with any characters except a through z?

This will help you find a regex that can do what you want.

I'm no regex expert but I think if it comes down to that and you have all your constraints, we can build one, experiment and make it work together.



-Dan

Quote: Originally Posted by dlite922 That's pretty difficult to do, if not impossible unless you find some other pattern in your string. use preg_replace() http://us2.php.net/preg_replace to implent some kind of pattern... for example does it always end with t, those that end with "t" do not replace? does it have to end with "-" everytime? should it end with any characters except a through z? This will help you find a regex that can do what you want. I'm no regex expert but I think if it comes down to that and you have all your constraints, we can build one, experiment and make it work together. -Dan

Yes you are right.

I am using -->