Trying To Prevent Duplicate Values To Be Added To An Array.

Having an issue with my project when it comes to adding a duplicate value to an array on a click event. when I push the clicked item's value to the array openedCards.push(card); th

Solution 1:

With vanilla javascript you can do this like the following:

if (array.indexOf(value) === -1) array.push(value);

Where array is your array of value's that you don't want duplicates of.

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Or, you can use the following es6 syntax:

if (array.includes(value) === false) array.push(value);

Solution 2:

I think you are running into issues with using object reference vs value

While obj and obj2 have same value for underlying properties, they both return different values to $.inArray

arr = [];
obj = {}; obj.A = 2;
arr.push(obj);
obj2 = {}; obj2.A = 2;
console.log($.inArray(obj, arr)); // 0
console.log($.inArray(obj2, arr)); // -1

In this case, I would recommend using some other property of card to check for availability within the array

function containsCard(card, list) {​
   return list.some(function(elem) {
        return elem.A === card.A
   })
}

arr = [];
obj = {}; obj.A = 2;
arr.push(obj);
obj2 = {}; obj2.A = 2;
console.log(containsCard(obj, arr)); // true
console.log(containsCard(obj2, arr)); // true

Solution 3:

You can just use $.inArray(), like:

if(!$.inArray(value, array))array.push(value);