Declared value exists in array? HELP!

[stephdumais]

Hi, I'm having trouble figuring this out. I want my script to do two things:

Compare a value to values in an array.
If the declared value exists in the array, I would like to return it's associated key.
If it doesn't I want to simply return the value itelf.

EXAMPLE:

arrayexample = array (
'mike' => 'one',
'joe' => 'two',
'eva' => 'three'
);

If $value declared is 'joe', return 'two'
if $value declared is 'steph', return 'steph'

Can anyone help?
Thanks!

[drawmack]

http://us3.php.net/manual/en/function.in-array.php

[stephdumais]

Thanks for the function tip, but how do I return the value's corresponding key in the array once the value has been found to be existing?

[drawmack]

<?php
function array_key ($needle,$haystack,$failure = 0) {
     //if needle is a null string fail with error message
     if ($needle == "") {
        echo "array_key ->You must provide a value to search the array for.<br />\n"
        return $failure;
    //if needle is an array fail with error message
    } elseif (is_array($needle)) {
      echo "array_key -> Needle cannot be an array.<br />\n";
      return $failure;
    }
    //if haysstack is not an array or is empty fail with error message
    if (!is_array($haystack) || count($haystack) < 1)) {
       echo "array_key -> Haystack must be an array with at least one entry in it.<br />\n";
       return $failure;
    }

//function assumes failure
$retval = $failure;

//test each key for success
foreach(array_keys($haystack) as $curIndex) {
  //on success update the return value to reflect that
  if($haystack[$curIndex] == $needle) {$retval = $curIndex;}
} //end foreach

   //return the key or $failure depending on the outcome of the
  //function.
    return $retval
}  //end array_key

there you go, failure is optional and will be zero if ommitted

[stephdumais]

Ok, I fixed a few parse errors you had, then took out the error handling and reduced your code to it's simplest expression and came up with this:

<?php
$names = array('helen' => 'one','adam' => 'two');
function array_key ($value,$names) {
//test each key for success
foreach(array_keys($names) as $curIndex) {
//on success update the return value to reflect that
if($names[$curIndex] == $value) {$retval = $curIndex;}
} //end foreach
return $retval;
} //end array_key
array_key ($value,$names);
?>

I loaded this page with value=helen in the query string and it returns nothing. Is there anything missing?

[drawmack]

you would want value = 'one' which would return the key of 'helen' not value = 'helen' which will return the value of failure.

Additionally, why did you remove the error checking?

[stephdumais]

I simply removed it because it didn't seem to work initialy, so I stripped it down to basics in order to find any errors.
It still doesn't work 🙁

[drawmack]

try putting in some echo statements to see what is going on with each iteration of the loop.

maybe

echo |\$key = $curIndex, \$value = $Value, \$name[$curIndex] = " . $name[$curIndex] . "<br />";

[stephdumais]

Something's not right in that line. I'll reformulate my question in a new post and see what others think.

Or if you don`t mind, could you test the code yourself online? Maybe you'll see what's not ticking right...

[drawmack]

yeah I'll do that from work in a couple hours

[drawmack]

It's working for me and all that I did was correct the parse error, although I did make it case insensitive.

Please see attached example.

[stephdumais]

Excellent, after getting rid of the form and html, I made this into a function that works great for my application.
Thanks!!!