function isSpace(checkstr) {
  var str = '';
  for(i = 0; i < checkstr.length; i++) {
    str = str + ' ';
  }
  return (str == checkstr);
}


function isInteger(s)
{   var i;
    for (i = 0; i < s.length; i++)
    {   
        // Check that current character is number.
        var c = s.charAt(i);
        if (((c < "0") || (c > "9"))) return false;
    }
    // All characters are numbers.
    return true;
}

 
function validateEmail(email)
{
	if (email.charAt(0)=="."
		|| email.charAt(0)=="@"
		|| email.indexOf('@', 0) == -1 
		|| email.indexOf('.', 0) == -1 
		|| email.lastIndexOf("@")==email.length-1 
		|| email.lastIndexOf(".")==email.length-1)
	{
		return false;
	}
	return true;
}

function checkPassword (password) {
	
	var illegalChars = /[\W_]/; // allow only letters and numbers
	if ((password.length < 6) || (password.length > 16) || illegalChars.test(password)) {
		return false;
	}else{
		return true;
	}
}