Simple base converter

base.php

Decimal: <input type="text" name="decimal"/>
Converting to base:
<select name="base">
<option value="2">2 - Binary</option>
<option value="8">8 - Octal</option>
<option value="16">16 - Hexadecimal</option>
</select>
<input type="submit" />
</form>
</p>

<?
  $keys = array(0,1,2,3,4,5,6,7,8,9,'A','B','C','D','E','F'); // Values to convert to, this is a hack of a way to do base conversion but it works.

  if(is_numeric($_POST["decimal"])){ // Make sure the input is a number

    // Have to convert from str to int!
    $dec = intval($_POST["decimal"]);
    $base = intval($_POST["base"]);

    // Lets do Math!!!!!
    while(intval($dec) != 0) {
      $output .= strval($keys[$dec % $base]);
      $dec /= $base;
    }

    // Switch statements make code nasty, but in this case it was faster to use.
    switch($base) {
      case 2:
        $base_w = "binary";
        $base_m = "0b";
        break;
      case 8:
        $base_w = "octal";
        $base_m = "0o";
        break;
      case 16:
        $base_w = "hexadecimal";
        $base_m = "0x";
        break;
    }

    // Display the results
    echo $_POST["decimal"] . " in " . $base_w . " is " . $base_m . strrev($output);

  } elseif(isset($_POST["decimal"])) {
    echo "That is not a number you douchewank!";
  }
?>

<p>
  <a href="http://gist.github.com/956448">Source Code</a>
</p>

This is a simple base converter, I wrote it in about 10 minutes so its not as clean as it could be. Live demo at http://jacobatkins.com/base.php