function forwardLink(frmLinks){
//function to forward links from a dropdown menu
//ensure form is called "frmLinks" and select is called "selWebpage"

	var URL = document.frmLinks.selWebpage.options[document.frmLinks.selWebpage.selectedIndex].value; 
	window.location.href = URL; 
}

function HideMenu(DivId) {
//function to hide div
//ensure images are called "PlusImage" and "MinusImage"
	if(DivId.length < 1) { 
    	return; 
  	}
  	document.getElementById(DivId).style.display = "none";
  	var PlusImage = DivId + "_Plus";
	var MinusImage = DivId + "_Minus";
	document.getElementById(PlusImage).style.display="inline";
	document.getElementById(MinusImage).style.display="none";
}

function ShowMenu(DivId) {
//function to show div
//ensure images are called "PlusImage" and "MinusImage"
	if(DivId.length < 1){ 
    	return;
  	}
  	document.getElementById(DivId).style.display = "inline";
  	var PlusImage = DivId + "_Plus";
  	var MinusImage = DivId + "_Minus";
	document.getElementById(MinusImage).style.display="inline";
	document.getElementById(PlusImage).style.display="none";
}

function addOne(inputId,sign){
//function to add 1 or minus 1 in water meter calculator (meter_calc)
	var inputVal;
	var validChars="0123456789";
	var newVal;

	inputObj = document.getElementById(inputId);
	inputVal = inputObj.value;
	if (inputVal==""){
		document.getElementById(inputId).value = "1";
	}else{
		for (n=0; n<validChars.length; n++) {
			if (validChars.indexOf(inputVal.charAt(n))==-1) {
				alert("Please input numbers only");
				break;
			} else {				
				if (sign=="add"){	
					newVal = parseInt(document.getElementById(inputId).value) + 1;
				}else{
					newVal = parseInt(document.getElementById(inputId).value) - 1;
					if (newVal== -1){
						newVal=0;
					}
				}
				document.getElementById(inputId).value = newVal;
				break;
			}
		}
	}
}