slice() Array instance method
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slice()
Description
Returns a new array comprising of a single depth section of an existing array.
- Any modifications to the new array has no affect on the arrays it was created from.
- Any modifications to the old array has no affect on the new array created from them.
- Modifications to an object whose reference is held within the arrays will affect both arrays.
Syntax
| Signature | Description |
|---|---|
anArray.slice(begin[, end]) | Returns a new array comprising of a single depth section of an existing array. |
Parameters
| Parameter | Description |
|---|---|
begin | The starting extraction position of the zero-based index. Negative values start extraction from the end of the index backwards, for the number after negation. |
end | The ending extraction position of the zero-based index. The ending position pertains to the index to stop before or for negative values the elements to miss from end. When omitted extraction is to end of array. |
Examples
The code below creates new arrays containing sections of the initial array.
// Create an array of days of the week.
var week = ['Mon', 'Tues', 'Wed', 'Thurs', 'Fri', 'Sat', 'Sun'];
/*
Create array of middle 3 days of week.
Slice stops after 5th elem. (Fri).
var midDays = ['Wed', 'Thurs', 'Fri'];
/*
var midDays = week.slice(2,5);
/*
Create array of middle 3 days of week.
Slice misses last 2 elements.
var middleDays = ['Wed', 'Thurs', 'Fri'];
/*
var middleDays = week.slice(2,-2);
/*
Create array of weekend days.
Slice will extract last 3 elements.
var weekendDays = ['Fri', 'Sat', 'Sun'];
/*
var weekendDays = week.slice(-3);
alert(midDays + ' - ' + middleDays + ' - ' + weekendDays);
Related Tutorials
JavaScript Intermediate Tutorials - Lesson 1 - Arrays