Im building an automatic pagination calculator that calculates offset and range according to user input. A very simple task but my algorithm is off. You can try this by entering any number and you will see the numbers do not completely add up. How can I make this work?
//event listener
var button = document.getElementById('submit');
//click
button.addEventListener('click',function(){
//div results
var results = document.getElementById('results');
//clear div before appending
results.innerHTML= '';
//grab value
var total_items = document.getElementById('total_items').value;//331165139
var per_page = document.getElementById('items_per_page').value;
//total pages
var total_pages = Math.ceil(total_items/per_page);
//iterate over pages
for(var x = 0; x<total_pages; x++){
//get page
var page = x+1;
//offset
var offset = (per_page * page) - per_page;
//range from
var from = ((page - 1) * per_page) + 1 ;
//range to
var to = per_page * page
var range = from + ' - ' + to;
//creating divs
var newDiv = document.createElement('div');
newDiv.innerHTML = 'page : ' + page + ' | offset : ' + offset + ' | range : ' + range + ' | total : ' + (to-from);
results.appendChild(newDiv);
}
})<h3>Pagination Calculator</h3>
<hr>
<p>Calculates pagination automatically in the console</p>
<p>*Pop open the console</p>
<hr>
<label>total items </label>
<input id="total_items">
<label>limit per page</label>
<input id="items_per_page">
<button id="submit">Submit</button>
<hr>
<div id="results"></div>