function for checking begg. and end of a string

[dsaba]

I searched google and php.net but I suppose I don't have the right keywords for what function I want

 

I wanted to ask if anyone knew the best method or best php function to read the begg. and end of a string.

 

for example:

$string = "<<hello world>>";

 

I want to make sure that the first 2 characters of this string are "<<"

I also want to make sure that the last 2 characters are ">>"

If this is not true then I want to reject or echo an error message.

 

I know how to check if certain characters exist in a string, and even replace them, but I want to check if certain characters exist in the begg. or end of a string.

 

-thanks in advance

[redarrow]

use eregi or preg_match ok.

[paul2463]

function check_string($str)
{
$num = strlen($str)-2;
$begin = substr($str,0,2);
$end = substr($str,$num);
if (($begin == "<<")&&($end==">>"))
{
return true;
}
else
{
return false;
}
}

$string = "<<hello world>>";
if(check_string($string)
{
//do stuff in this case as it will return true on $string
}
else
{
//error message
}

[dsaba]

*edit

(removed my question for an example, since right before I posted paul did show me an example)

 

thanks

[paul2463]

thats what my check_function($string) does for you

 

function check_string($str) // pass the function the string to check
{
$num = strlen($str)-2; // count the number of characters in the string then assign the variable $num with this number - 2
$begin = substr($str,0,2); //strip out the first two characters and assign to $begin
$end = substr($str,$num); //strip out the last two characters and assign to $end
if (($begin == "<<")&&($end==">>")) 
{ 
return true;
}
else
{
return false;
}
}

[dsaba]

is there also a way I can delete the rest of the string from << and on

 

for example:

$string = "<<hello world>>";

 

I want to keep "<<"

but delete the rest

 

also another thing I want to do is add on from there as well

for example:

$string = "<<hello world>>";

 

Only after the "<<" I want to add "hola mundo en espanol"

 

so the string will now read "<<hola mundo en espanol hello world>>"

 

can you show me an example with that?

[redarrow]

Be back in 5 min tell me what it all means ok?

<?php

$word="<< hi there i am redarrow use preg_match or eregi >>";

if (eregi("^<<.[a-z0-9]{0,100}.+>>$",$word)){

echo "correct";

}else{

echo"not correct";

}
?>

[dsaba]

no worries

I think you meant that you will tell me what it all means?

or did you want me to tell you what it means?

 

because regex is one of my weakness, i don't know the syntax, so i try to stay away from it (for now)

[redarrow]

ARE YOU HAPPY NOW M8?