Live Demo: add-or-remove-array-elements-at-any-index

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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="utf-8">
    <title>JavaScript Add or Remove Array Elements at any Index</title>
</head>
<body>
    <script>
    let colors = ["Red", "Green", "Blue"];
    let removed = colors.splice(0,1); // Remove the first element
     
    document.write(colors + "<br>"); // Prints: Green,Blue
    document.write(removed + "<br>"); // Prints: Red (one item array)
    document.write(removed.length + "<br>"); // Prints: 1
     
    removed = colors.splice(1, 0, "Pink", "Yellow"); // Insert two items at position one
    document.write(colors + "<br>"); // Prints: Green,Pink,Yellow,Blue
    document.write(removed + "<br>"); // Empty array
    document.write(removed.length + "<br>"); // Prints: 0
     
    removed = colors.splice(1, 1, "Purple", "Voilet"); // Insert two values, remove one
    document.write(colors + "<br>"); //Prints: Green,Purple,Voilet,Yellow,Blue
    document.write(removed + "<br>"); // Prints: Pink (one item array)
    document.write(removed.length); // Prints: 1
    </script>
</body>
</html>

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