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javascript - Returning an array without a removed element? Using splice() without changing the array?

I want to do something like:

var myArray = ["one","two","three"];
document.write(myArray.splice(1,1));
document.write(myArray);

So that it shows first "one,three", and then "one,two,three". I know splice() returns the removed element and changes the array, but is there function to return a new array with the element removed? I tried:

window.mysplice = function(arr,index,howmany){
    arr.splice(index,howmany);
    return arr;   
};

If I try:

var myArray = ["one","two","three"];
document.write(mySplice(myArray,1,1));
document.write(myArray);

It still changes myArray.

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1 Answer

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You want slice:

Returns a one-level deep copy of a portion of an array.

So if you

a = ['one', 'two', 'three' ];
b = a.slice(1, 3);

Then a will still be ['one', 'two', 'three'] and b will be ['two', 'three']. Take care with the second argument to slice though, it is one more than the last index that you want to slice out:

Zero-based index at which to end extraction. slice extracts up to but not including end.


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