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I am just documenting things what i learned online in here. I do express things in my own words. And I create my own program samples which serves as my practice. I do this so that when someday I would need some notes to review, I can just visit in h...

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Useful Array functions

Start from the beginning

by ShinkokuEndo

                                        
                                                  };
function practicingArray(){
    let list1 = array.splice(0, 3, "apple", "banana", "chery");
    let list2 = array.slice(0, 2);
    let list3 = array.concat("draw", "element", "frame");
    let list4 = list3.concat(object1);
    document.writeln(list1);
    document.writeln(list2);
    document.writeln(list3);
    document.writeln(list4);
    document.writeln(array);
}
======================
HTML
practicingArray()
Result:
1,2,3 apple,banana apple,banana,chery,draw,element,frame apple,banana,chery,draw,element,frame,green,heaven,india,joker apple,banana,chery
Note: The displays are as follows: array, list2, list3, list4, list1

4. forEach(function(value, index, array){ // no return statements; })
    - you can use the forEach function to iterate throught the array. index is the key. value is the element's value. array is your array.
====================
let array = [1, 2, 3];
let object1 = {
    0: "green",
    1: "heaven",
    2: "india",
    3: "joker",
    [Symbol.isConcatSpreadable]: true,
    length: 4
};
function practicingArray(){
    let list1 = array.splice(0, 3, "apple", "banana", "chery");
    let list2 = array.slice(0, 2);
    let list3 = array.concat("draw", "element", "frame");
    let list4 = list3.concat(object1);
    list4.forEach((value, index, _) => {document.writeln('index${index}: ${value},')});
}
====================
HTML
practicingArray()
Result:
index0: apple, index1: banana, index2: chery, index3: draw, index4: element, index5: frame, index6: green, index7: heaven, index8: india, index9: joker,
5. indexOf(value)
    - it returns the index of the element where counting starts from zero to last index.
6. lastIndexOf(value)
    - it returns the index of the element where counting starts from last to zero index.
7. includes(value)
    - it returns true if the value is within the array.
8. find(function(value, index, array){ // boolean statement; })