I have a list of n items. Each item has a title with the format [first part] - [color]. Items have unique colors.
<div class="the-elements">
<div class="elem" data-splittitle="Alfa Romeo" data-splitcolor="Red">Alfa Romeo - Red</div>
<div class="elem" data-splittitle="BMW" data-splitcolor="Red">BMW - Red</div>
<div class="elem" data-splittitle="Fiat " data-splitcolor="Blue">Fiat - Blue</div>
<div class="elem" data-splittitle="Alfa Romeo" data-splitcolor="Black">Alfa Romeo - Black</div>
<div class="elem" data-splittitle="Alfa Romeo" data-splitcolor="Silver">Alfa Romeo - Silver</div>
<div class="elem" data-splittitle="Alfa Romeo" data-splitcolor="Some Color">Alfa Romeo - Some Color</div>
<div class="elem" data-splittitle="Alfa Romeo" data-splitcolor="Some other Color">Alfa Romeo - Some other Color</div>
<div class="elem" data-splittitle="BMW" data-splitcolor="Green">BMW - Green</div>
<div class="elem" data-splittitle="Zastava" data-splitcolor="Black">Zastava - Black</div>
<div class="elem" data-splittitle="BMW" data-splitcolor="Silver">BMW - Silver</div>
<div class="elem" data-splittitle="Fiat" data-splitcolor="Silver">Fiat - Silver</div>
<div class="elem" data-splittitle="Fiat" data-splitcolor="Red">Fiat - Red</div>
<div class="elem" data-splittitle="BMW" data-splitcolor="Orangered">BMW - Orangered</div>
... ...
...
</div>
I want to achieve the following:
<div class="the-elements">
<div class="elem" data-splittitle="Alfa Romeo" data-splitcolor="Red">Alfa Romeo - <span class="occurence">has 5 colors</span></div>
<div class="elem" data-splittitle="BMW" data-splitcolor="Red">BMW - <span class="occurence">has 4 color</span></div>
<div class="elem" data-splittitle="Fiat " data-splitcolor="Blue">Fiat - <span class="occurence">has 3 color</span></div>
<div class="elem" data-splittitle="Alfa Romeo" data-splitcolor="Black">Alfa Romeo - <span class="occurence">has 5 color</span></div>
<div class="elem" data-splittitle="Alfa Romeo" data-splitcolor="Silver">Alfa Romeo - <span class="occurence">has 5 color</span></div>
<div class="elem" data-splittitle="Alfa Romeo" data-splitcolor="Some Color">Alfa Romeo - <span class="occurence">has 5 color</span></div>
<div class="elem" data-splittitle="Alfa Romeo" data-splitcolor="Some other Color">Alfa Romeo - <span class="occurence">has 5 color</span></div>
<div class="elem" data-splittitle="BMW" data-splitcolor="Green">BMW - <span class="occurence">has 4 color</span></div>
<div class="elem" data-splittitle="Zastava" data-splitcolor="Black">Zastava - <span class="occurence">has 1 color</span></div>
<div class="elem" data-splittitle="BMW" data-splitcolor="Silver">BMW - <span class="occurence">has 4 color</span></div>
<div class="elem" data-splittitle="Fiat" data-splitcolor="Silver">Fiat - <span class="occurence">has 3 color</span></div>
<div class="elem" data-splittitle="Fiat" data-splitcolor="Red">Fiat - <span class="occurence">has 3 color</span></div>
<div class="elem" data-splittitle="BMW" data-splitcolor="Orangered">BMW - <span class="occurence">has 4 color</span></div>
... ...
...
</div>
The method i want to achieve the above is by counting how many times the first part appears. For example, i count n times [first part] which also means there are equal number of n colors for that item, since colors are unique for each [first part].
So what i am looking for is to count the occurrence of [first part]. I have searched Stack Overflow for similar q/a like: this, this, this or this
So i think of doing something like this:
// 1-make a nodelist of the elements i want
let elementNodeList = document.querySelectorAll('.elem');
// 2-turn the nodelist to array so i can use array functions like reduce, filter, etc
let elementArray = Array.from(elementNodeList);
// 3-loop my elements
elementArray.forEach((elem) => {
// 4-get the splittitle of the element
let elemSplitTitle = elem.dataset.splittitle;
// 5-compare and store this element splittitle against the entire array of elements for occurrence
let numOfOccurance = getOccurrence(productsArray, elemSplitTitle );
console.log(numOfOccurance);
// 6-display the result
elem.querySelector('.occurence').textContent = `IN ${numOfOccurance} COLORS`;
});
function getOccurrence(array, value) {
return array.filter((v) => (v === value)).length;
}
But the result is always 0. Obviously there is something i do not understand and i need some help to make it clear. I tried this also with
function getOccurrence(array, value) {
var count = 0;
array.forEach((v) => (v === value && count++));
return count;
}
// 1-make a nodelist of the elements i want
let elementNodeList = document.querySelectorAll('.elem');
// 2-turn the nodelist to array so i can use array functions like reduce, filter, etc
let elementArray = Array.from(elementNodeList);
// 3-loop my elements
elementArray.forEach((elem) => {
// 4-get the splittitle of the element
let elemSplitTitle = elem.dataset.splittitle;
// 5-compare and store this element splittitle against the entire array of elements for occurrence
let numOfOccurance = getOccurrence(elementArray, elemSplitTitle );
console.log(numOfOccurance);
// 6-display the result
elem.querySelector('.occurence').textContent = `IN ${numOfOccurance} COLORS`;
});
function getOccurrence(array, value) {
return array.filter((v) => (v === value)).length;
}
<div class="the-elements">
<div class="elem" data-splittitle="Alfa Romeo" data-splitcolor="Red">Alfa Romeo - <span class="occurence">has 5 colors</span></div>
<div class="elem" data-splittitle="BMW" data-splitcolor="Red">BMW - <span class="occurence"></span></div>
<div class="elem" data-splittitle="Fiat " data-splitcolor="Blue">Fiat - <span class="occurence"></span></div>
<div class="elem" data-splittitle="Alfa Romeo" data-splitcolor="Black">Alfa Romeo - <span class="occurence"></span></div>
<div class="elem" data-splittitle="Alfa Romeo" data-splitcolor="Silver">Alfa Romeo - <span class="occurence"></span></div>
<div class="elem" data-splittitle="Alfa Romeo" data-splitcolor="Some Color">Alfa Romeo - <span class="occurence"></span></div>
<div class="elem" data-splittitle="Alfa Romeo" data-splitcolor="Some other Color">Alfa Romeo - <span class="occurence"></span></div>
<div class="elem" data-splittitle="BMW" data-splitcolor="Green">BMW - <span class="occurence"></span></div>
<div class="elem" data-splittitle="Zastava" data-splitcolor="Black">Zastava - <span class="occurence"></span></div>
<div class="elem" data-splittitle="BMW" data-splitcolor="Silver">BMW - <span class="occurence"></span></div>
<div class="elem" data-splittitle="Fiat" data-splitcolor="Silver">Fiat - <span class="occurence"></span></div>
<div class="elem" data-splittitle="Fiat" data-splitcolor="Red">Fiat - <span class="occurence"></span></div>
<div class="elem" data-splittitle="BMW" data-splitcolor="Orangered">BMW - <span class="occurence"></span></div>
... ...
...
</div>