I'm trying to create a way to show the number of elements for each page, for example:
Page1: 1-5 elements of 327
Page2: 6-10 elements of 327
....
Now I have the opportunity to go to the nextPage, previousPage, lastPage, firstPage, and also the possibility to choose the number of element for every page(for example 5, 10, 20) (this.elementsForPage)
I have tried to create in this way:
if(action === "next"){
this.firstElement += parameters.length
this.lastElement += parameters.length
}
if(action === "previous"){
this.firstElement -= parameters.length
this.lastElement -= parameters.length
}
if(action === "last"){
this.firstElement = this.totalElements - this.parameters.length
this.lastElement = this.totalElements
}
if(action === "first"){
this.firstElement = 1;
this.lastElement = parameters.length
}
this works if I make next, previous and first. But it doesn't work If I go on the last page.
This is why If I go to the last page and it has only 2 results, for example, i'll have
firstElement = 327 - 2 = 325
lastElement = 327
But if I go on "previous" it counts:
firstElement = 325 - 5 = 320
lastElement = 327 - 5 = 322
and it is wrong because are showing 5 results not 2.
In your opinion how can I fix these problems?
This Function
function getCurrentPageItems(currentPage,perPage,total)
{
currentPage = currentPage - 1;
let elStart = currentPage*perPage +1;
let elEnd = elStart+perPage - 1;
elEnd = Math.min(Math.max(elEnd, 1), total);
console.log(`Page ${(currentPage+1)}: ${elStart}-${elEnd} of ${total}`);
return [elEnd,elEnd];
}
getCurrentPageItems(1,5,327);
getCurrentPageItems(2,5,327);
getCurrentPageItems(65,5,327);
getCurrentPageItems(66,5,327);
console.log(327/5);