find tags in a string

[mike1313]

I want to be able to take a string and find out if they used a < b > tag. If that tag is used and the closing tag isn't </ b >. Then it adds it to the string.

 

For ex.

$string = "<b>Hi.";
$add .="</b>";
$newstringafterwouldbe = "<b>Hi.</b>";

 

Just pointing me in the right direction on which function/s to use would be very helpful.

[papaface]

What could it be instead of

</b>

???

[mike1313]

No. The string will be users input and I'm allowing <B><U><I><S> only. What they post gets displayed on the page and I dont want them doing.

 

<B><S>What's up?

 

Without including the closing </B></S>, because in most cases it will mess things up.

[papaface]

How is the script supposed to know where to end the tags?

[mike1313]

At the end of the string so

$_POST[txt] = "<b>Hey";
$string = $_POST[txt];
  if(condition == true){
   $string .= "</b>";
  }
  else {
  $string .= "";
  }

 

something along those lines

[raku]

You could look for the < /b>, then if it isn't found, add it on the end.

 

if(strpos($string, "<b>") !== false && strpos($string, "</b>") !== false)
{
$string.="</b>";
}

 

Hope this helps.