Human-format currency $'s converted to machine floating points

currency-to-float.php

<?php
/*
 * Human-format currency $'s converted to machine floating points
 */

// Dollar amount via GET (not very secure)
$raw_dollar_amount = ( isset($_GET['dollar_amount']) ) ? htmlentities( $_GET['dollar_amount'], ENT_QUOTES, 'UTF-8' ) : FALSE;
if ( $raw_dollar_amount ) {
    // Create a return value in case nothing done
    $float_dollar_amount = $raw_dollar_amount;
    
    // Build string of only the separators
    $separators_only = preg_filter( '/[^,\.]/i', '', $raw_dollar_amount );
    
    /*
     *
     * Check # of separators
     * If more than one, position determines region
     *
     * NOTE: Am assuming no separators in the decimal portion
     * 	That could be problem for complex #'s, but this isn't physics class after all
     * 	
     */
    if ( strlen( $separators_only ) > 1 ) {
	if ( substr( $separators_only, 0, 1) == '.' ) {
	    $float_dollar_amount = str_replace( '.', '', $float_dollar_amount );
	    $float_dollar_amount = str_replace( ',', '.', $float_dollar_amount );
	    
	} else if ( substr( $separators_only, 0, 1) == ',' ) {
	    $float_dollar_amount = str_replace( ',', '', $float_dollar_amount );
	}
	
    } else if ( strlen( $separators_only ) == 1 && $separators_only == ',' ) {
	/*
	 * Here's the crux assumption made for fule prices:
	 * 	That "4.99", "4.9999" or "4,999" is likely to be float "4.9{999}"
	 *
	 * Other option is to measure # digits after the separator
	 * ...but then we hit same problem as prev regex:
	 * 	http://www.php.net/manual/en/function.floatval.php#85346
	 *
	 */
	$float_dollar_amount = str_replace( ',', '.', $float_dollar_amount );
    }
    
    // Output trackers & processed value
    echo "<h2>Raw &amp; Filtered Values</h2>";
    echo "Float $-value: $float_dollar_amount<br /><br />";
    echo "Raw input $-value: $raw_dollar_amount<br />";
    echo "Separators from raw input: $separators_only<br /><br />";
}


// Input form
?>
<h2>Input a $-amount here</h2>
<form id="dollar_input" name="dollar_input" action="<?php echo $_SERVER['PHP_SELF']; ?>" method="get">
    <input type="text" name="dollar_amount" />
    <input type="submit" value="Submit" />
</form>

Understood. I might have added different parsing code for each number type, but I saw your comment about 1,200 lines ... a lot for a plugin to track fuel & mileage.

I'm up past 1800 lines now. I expect to pass 2000 before the plugin gets released. Lots of fancy features. :)