<!--
function emailcheck(emailstr){
	
	var At = "@";
	var Dot = ".";
	var locationAt = emailstr.indexOf(At);
	var locationDot = emailstr.indexOf(Dot);

	// Get the index of the last dot in the email addres
	var locationLastDot = emailstr.lastIndexOf(Dot);

	var lengthStr = emailstr.length;	

	// Get the email alias substring from the given email address
	var emailAlias = emailstr.substring(0,locationAt);

	// Get the top-level domain name from the given email address
	var topLevelName = emailstr.substring((locationLastDot+1),lengthStr);


	if(emailstr.indexOf(At)==-1 || emailstr.indexOf(At)==0 || emailstr.indexOf(At)==lengthStr){
		alert("Please enter your valid email address.");
		return false;
	}
	
	if(emailstr.indexOf(Dot)==-1 || emailstr.indexOf(Dot)==0 || emailstr.indexOf(Dot)==lengthStr){
		alert("Please enter your valid email address.");
		return false;
	}

	// Look for a second '@' after the first expected '@'
	if(emailstr.indexOf(At,(locationAt+1))!=-1){
		alert("Please enter your valid email address.");
		return false;
	}

	// Look for a '.' at least two indexes after the '@'	
	if(emailstr.indexOf(Dot,(locationAt+3))==-1){
		alert("Please enter your valid email address.");
		return false;
	}
	
	// Check for any blank spaces in the given email address
	if(emailstr.indexOf(' ')!=-1){
		alert("Please enter your valid email address.");
		return false;
	}
	
	// The substring of the given email alias before the '@' must be at least two characters
	if(emailAlias.length < 2){
		alert("Please enter your valid email address.");
		return false;
	}
	
	/* The substring or the top-level domain name of the given email address after the @ must be
	    at least two characters. This allows for two letter country codes. */
	if((topLevelName.length < 2) || (topLevelName.length > 3)){
		alert("Invalid top-level domain name. Please reenter your email address.");
		return false;
	}

	// Check for any ','
	if(emailstr.indexOf(',')!=-1){
		alert("Your email address has a ',' in it. Please reenter your email address.");
		return false;
	}
	
	// Check for any '#'
	if(emailstr.indexOf('#')!=-1){
		alert("Your email address has a '#' in it. Please reenter your email address.");
		return false;
	}

	// Check for any '!'
	if(emailstr.indexOf('!')!=-1){
		alert("Your email address has a '!' in it. Please reenter your email address.");
		return false;
	}

	// Check for any '$'
	if(emailstr.indexOf('$')!=-1){
		alert("Your email address has a '$' in it. Please reenter your email address.");
		return false;
	}

	// Check for any '%'
	if(emailstr.indexOf('%')!=-1){
		alert("Your email address has a '%' in it. Please reenter your email address.");
		return false;
	}

	// Check for any '^'
	if(emailstr.indexOf('^')!=-1){
		alert("Your email address has a '^' in it. Please reenter your email address.");
		return false;
	}

	// Check for any '&'
	if(emailstr.indexOf('&')!=-1){
		alert("Your email address has a '&' in it. Please reenter your email address.");
		return false;
	}

	// Check for any '*'
	if(emailstr.indexOf('*')!=-1){
		alert("Your email address has a '*' in it. Please reenter your email address.");
		return false;
	}

	// Check for any '+'
	if(emailstr.indexOf('+')!=-1){
		alert("Your email address has a '+' in it. Please reenter your email address.");
		return false;
	}

	// Check for any '='
	if(emailstr.indexOf('=')!=-1){
		alert("Your email address has a '=' in it. Please reenter your email address.");
		return false;
	}	

	// Check for any '(' or ')'
	if(emailstr.indexOf('(')!=-1 || emailstr.indexOf(')')!=-1){
		alert("Your email address has either a '(' or ')' in it. Please reenter your email address.");
		return false;
	}

	// Check for any '<' or '>'
	if(emailstr.indexOf('<')!=-1 || emailstr.indexOf('>')!=-1){
		alert("Your email address has either a '<' or '>' in it. Please reenter your email address.");
		return false;
	}
	
	// Check for any '?' or '/'
	if(emailstr.indexOf('?')!=-1 || emailstr.indexOf('/')!=-1){
		alert("Your email address has either a '?' or '/' in it. Please reenter your email address.");
		return false;
	}

	// Check for any '[' or ']'
	if(emailstr.indexOf('[')!=-1 || emailstr.indexOf(']')!=-1){
		alert("Your email address has either a '[' or ']' in it. Please reenter your email address.");
		return false;
	}

	// Check for any '{' or '}'
	if(emailstr.indexOf('{')!=-1 || emailstr.indexOf('}')!=-1){
		alert("Your email address has either a '{' or '}' in it. Please reenter your email address.");
		return false;
	}

	// Check for any '|'
	if(emailstr.indexOf('|')!=-1){
		alert("Your email address has a '|' in it. Please reenter your email address.");
		return false;
	}	

	return true;	
}
-->