Update an HTML div using Javascript without refreshing the page

Question

I'm trying to make a simple rating system using php and javascript . the idea is to change the value of HTML div (number of rate) using javascript without refreshing the page , the problem is that i can't get the value of the HTML div . this is the div :

<div id="rating" >5565</div> 

and i try to get this value using javascript

function give_id_like() {
    var a = document.getElementById("rating").value;
    var c = a + 1;
    document.getElementById("rating").innerHTML = c;
}

but i get this result, for example if i have in the div 88 when i run the function i get this 881 if i run it again i get 8811 . what i want is when i run the function i want to get 89 and when i run it again 90 and so on .

Answer 1

This happens because value property returns String object. You need parseInt for this:

c = parseInt( a, 10 ) + 1;

Answer 2

You need to use parseInt()

function give_id_like() {
    var a = parseInt(document.getElementById("rating").value);
    var c = a + 1;
    document.getElementById("rating").innerHTML = c;
}