function isAlpha(c) 
{
	if ((c >= "A" && c <= "Z") || (c >= "a" && c <= "z") )
	{ 
		return true; 
	}
	return false;
}

function isDigit(c) 
{
	var test = "" + c;
	if (test >= "0" && test <= "9") 
	{ 
		return true; 
	}
	return false;
}



function isValidLogin(s) {
  var test = "" +s;
  for (var k = 0; k < test.length; k++) {
	var c = test.substring(k, k+1);
	if((isAlpha(c) == true) || (c == '-') ||(c == 'ñ')||(c == ' ')||(isDigit(c) == true))
	{
	 continue;
    }
    else
	{
	 return false;
    }
  }
  return true;
}