Example
Do a global search for "ain" in a string, and output the index after a match is found:
var str = "The rain in Spain stays mainly in the plain";
var patt1 = /ain/g;
while (patt1.test(str)==true)
{
document.write("'ain' found. Index now at: "+patt1.lastIndex);
document.write("<br>");
}
The output of the code above will be:
'ain' found. Index now at: 8
'ain' found. Index now at: 17
'ain'
found. Index now at: 28
'ain' found. Index now at: 43
Try it Yourself »
Definition and Usage
The lastIndex property specifies the index at which to start the next match.
Note: This property only works if the "g" modifier is set.
This property returns an integer that specifies the character position immediately after the last match found by exec( ) or test( ) methods.
Note: exec( ) and test( ) reset lastIndex to 0 if they do not get a match.
Browser Support
| Property | |||||
|---|---|---|---|---|---|
| lastIndex | Yes | Yes | Yes | Yes | Yes |
Syntax
RegExpObject.lastIndex
Return Value
| Type | Description |
|---|---|
| Number | An integer that specifies the character position immediately after the last match found by exec( ) or test( ) methods |
Technical Details
| JavaScript Version: | 1.2 |
|---|
< JavaScript RegExp Object