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JavaScript - copy array with replace item operation
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In this article, we would like to show you how to copy an array with item replace operation using JavaScript.
Quick solution:
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var array = [1, 2, 3];2
var index = 1;3
var replacement = 4;4
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var result = array.map((value, i) => (i === index ? replacement : value));6
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console.log(result); // [1, 4, 3]
In this example, we create a reusable function that creates a copy of the given array and replaces the item with given index with the replacement.
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function replaceItem(array, index, replacement) {2
return array.map((value, i) => (i === index ? replacement : value));3
}4
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// Usage example:7
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var array = [1, 2, 3];9
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var copy1 = replaceItem(array, 0, 4);11
var copy2 = replaceItem(array, 0, 5);12
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var copy3 = replaceItem(array, 1, 6);14
var copy4 = replaceItem(array, 1, 7);15
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console.log(copy1); // [ 4, 2, 3 ]17
console.log(copy2); // [ 5, 2, 3 ]18
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console.log(copy3); // [ 1, 6, 3 ]20
console.log(copy4); // [ 1, 7, 3 ]
