[SOLVED] strpos effectiveness

[Ninjakreborn]

Is strpos() as affective as straight regular expressions for finding a basic string inside another string.

For example, validating filetypes (Other filetypes).

Say I wanted to allow only .mov, Is strpos checking for mov inside a filetype going to be safe, or testing for .mov.  Is this going to be as affective as setting it up to test with regular expressions?

[trq]

If you know the exact string your looking for strpos() is much more efficient.

[Ninjakreborn]

Good that is exactly what I wanted to hear.  Thanks.

[.josh]

One thing I like about the manual is that it is usually really good about telling you things like this. 

Tip

 

Do not use preg_match() if you only want to check if one string is contained in another string. Use strpos() or strstr() instead as they will be faster.

[effigy]

If you're checking for a string at the end of another string, regular expressions will be slightly easier on the eyes because you can use the \z anchor. If you use strpos, you'll need to calculate the results against both lengths to determine that it is, in fact, at the end.

[Ninjakreborn]

I know, but I am running it through an array.  I wanted to know if it's 100% safe.

I want to run it through something like.

 

$extensions = array(".wav",

                          ".mov",

                          ".swf"); // plus whatever else will be here

 

foreach ($extensions as $k => $v) {

  if (strpos($extensions, $file)) {

    req

 

 

}

ah whatever I will get it together when I get started, but that's the basic idea.  I am going to use strpos to validate the filetype's.

[Ninjakreborn]

If you're checking for a string at the end of another string, regular expressions will be slightly easier on the eyes because you can use the \z anchor. If you use strpos, you'll need to calculate the results against both length's to determine that it is, in fact, at the end.

I am just frustrated because I had an entire file handling system created I recopied, however accidentally deleted the source file's along time ago, and haven't gotten around to building another one.  This project is going to require me to rebuild another one, which I am looking for quicker way's to get this up and running.  I may just use regular expressions.

 

Thanks for all the advice.

[Ninjakreborn]

Incase if it help's anyone I created this

<?php
function getExtension($file) {
  $pos = strrpos($file, '.');
  if(!$pos) {
    return 'Unknown Filetype';
  }
  $str = substr($file, $pos, strlen($file));
  return $str;
}
?>

[trq]

If your wanting to validate valid filetypes using an array, use in_array(). eg;

 

 

<?php

  $file = 'foo.wav';
  $validtypes = array('wav','mov','swf');

  if (in_array(substr($file,-3),$validtypes)) {
    // is valid.
  }

?>