Name
RegExp.lastIndex — the starting position of the next match
Synopsis
regexp
.
lastIndex
Description
lastIndex
is a read/write
property of RegExp objects. For regular expressions with the “g”
attribute set, it contains an integer that specifies the character
position immediately following the last match found by the RegExp.exec()
and RegExp.test()
methods. These methods use
this property as the starting point for the next search they
conduct. This allows you to call those methods repeatedly, to loop
through all matches in a string. Note that lastIndex
is not used by RegExp objects
that do not have the “g” attribute set and do not represent global
patterns.
This property is read/write, so you can set it at any time to
specify where in the target string the next search should begin.
exec()
and test()
automatically reset lastIndex
to 0 when they fail to find a
match (or another match). If you begin to search a new string after
a successful match of some other string, you have to explicitly set
this property to 0.
See Also
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