Check either single email addresses or strings with multiple email addresses (coming from a textarea or similar)

check_emails.as

/* 
 * Check if supplied String is a valid email adress.
 * RegEx courtesy http://www.regular-expressions.info
 * 
 * Use like so: is_valid_email('[email protected]');
 */
function is_valid_email(inputEmail:String):Boolean {
	var emailRegEx:RegExp = /^[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,4}$/;
	//trace(emailRegEx.test(email));
	return emailRegEx.test(email);
}

/* 
 * Check if supplied String contains only valid email adresses, separated 
 * by commas, semi-colons, spaces, tabs and/or line breaks.
 * 
 * Use like so: are_valid_emails('[email protected] [email protected], [email protected]');
 */
function are_valid_emails(inputEmail:String):Boolean {
	var emailArray:Array = inputEmail.split(/,\s+|\s+|;\s+|\n+|\t+/);

	// must be at least one email present
	if (emailArray.length < 1) {
		   return false;
	}
	// validate each email address and return false if any address is not a valid email
	for (var i:Number = 0; i < emailArray.length; i++) {
		if (!is_valid_email(trim(emailArray[i]))) {
			return false;
		}
	}
	
	// all email adresses valid
	return true;
}

/*
 * Helper-function to trim spaces from both ends of a string.
 */
function trim(str:String):String
{
    for(var i = 0; str.charCodeAt(i) < 33; i++);
    for(var j = str.length-1; str.charCodeAt(j) < 33; j--);
    return str.substring(i, j+1);
}