Javascript [Electronic resources] : The Definitive Guide (4th Edition) نسخه متنی

Availability

JavaScript 1.2; JScript 5.5; ECMAScript v3

Synopsis

array.splice(start, deleteCount, value, ...)

Arguments

start

The array element at which the insertion and/or deletion is to begin.

deleteCount

The number of elements, starting with and including
start, to be deleted from
array. This argument is optional; if not
specified, splice( ) deletes all elements from
start to the end of the array.

value, ...

Zero or more values to be inserted into
array, beginning at the index specified by
start.

Returns

An array containing the elements, if any, deleted from
array. Note, however, that due to a bug,
the return value is not always an array in the Netscape
implementation of JavaScript 1.2.

Description

splice( ) deletes zero or more array elements
starting with and including the element
start and replaces them with zero or more
values specified in the argument list. Array elements that appear
after the insertion or deletion are moved as necessary so that they
remain contiguous with the rest of the array. Note that, unlike the
similarly named slice( ), splice(
) modifies array directly.

Example

The operation of splice( ) is most easily
understood through an example:

var a = [1,2,3,4,5,6,7,8]
a.splice(4);        // Returns [5,6,7,8]; a is [1,2,3,4]
a.splice(1,2);      // Returns [2,3]; a is [1,4]
a.splice(1,1);      // Netscape/JavaScript 1.2 returns 4 instead of [4]
a.splice(1,0,2,3);  // Netscape/JavaScript 1.2 returns undefined instead of []

Bugs

splice( ) is supposed to return an array of
deleted elements in all cases. However, in Netscape's
JavaScript 1.2 interpreter, when a single element is deleted it
returns that element rather than an array containing the element.
Also, if no elements are deleted, it returns nothing instead of
returning an empty array. Netscape implementions of JavaScript
emulate this buggy behavior whenever Version 1.2 of the language is
explicitly specified.

See Also

Array.slice( )