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

Availability

JavaScript 1.2; JScript 3.0; ECMAScript v3

Synopsis

string.slice(start, end)

Arguments

start

The string index where the slice is to begin. If negative, this
argument specifies a position measured from the end of the string.
That is, -1 indicates the last character, -2 indicates the second
from last character, and so on.

end

The string index immediately after the end of the slice. If not
specified, the slice includes all characters from
start to the end of the string. If this
argument is negative, it specifies a position measured from the end
of the string.

Returns

A new string that contains all the characters of
string from and including
start and up to but not including
end.

Description

slice( ) returns a string containing a slice, or
substring, of string. It does not modify
string.

The String methods slice( ), substring(
), and the deprecated substr( ) all
return specified portions of a string. slice( ) is
more flexible than substring( ) because it allows
negative argument values. slice( ) differs from
substr( ) in that it specifies a substring with
two character positions, while substr( ) uses one
position and a length. Note also that String.slice(
) is an analog of Array.slice( ).

Example

var s = "abcdefg";
s.slice(0,4)    // Returns "abcd"
s.slice(2,4)    // Returns "cd"
s.slice(4)      // Returns "efg"
s.slice(3,-1)   // Returns "def"
s.slice(3,-2)   // Returns "de"
s.slice(-3,-1)  // Should return "ef"; returns "abcdef" in IE 4

Bugs

Negative values for start do not work in
JScript 3.0 (Internet Explorer 4). Instead of specifying a character
position measured from the end of the string, they specify character
position 0.

See Also

Array.slice( ), String.substring( )