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Array.push() if does not exist?

How can I push into an array if neither values exist? Here is my array:
[

    { name: "tom", text: "tasty" },

    { name: "tom", text: "tasty" },

    { name: "tom", text: "tasty" },

    { name: "tom", text: "tasty" },

    { name: "tom", text: "tasty" }

]


If I tried to push again into the array with either name: "tom" or text: "tasty", I don't want anything to happen... but if neither of those are there then I want it to .push()

How can I do this?
json array javascript
by

2 Answers

vishaljlf39
You could extend the Array prototype with a custom method:
// check if an element exists in array using a comparer function

// comparer : function(currentElement)

Array.prototype.inArray = function(comparer) { 

    for(var i=0; i < this.length; i++) { 

        if(comparer(this[i])) return true; 

    }

    return false; 

}; 



// adds an element to the array if it does not already exist using a comparer 

// function

Array.prototype.pushIfNotExist = function(element, comparer) { 

    if (!this.inArray(comparer)) {

        this.push(element);

    }

}; 



var array = [{ name: "tom", text: "tasty" }];

var element = { name: "tom", text: "tasty" };

array.pushIfNotExist(element, function(e) { 

    return e.name === element.name && e.text === element.text; 

});
pankajshivnani123
For an array of strings (but not an array of objects), you can check if an item exists by calling .indexOf() and if it doesn't then just push the item into the array:

var newItem = "NEW_ITEM_TO_ARRAY";

var array = ["OLD_ITEM_1", "OLD_ITEM_2"];



array.indexOf(newItem) === -1 ? array.push(newItem) : console.log("This item already exists");



console.log(array)

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