JavaScript lastIndex Property
Example
let text = "The rain in Spain stays mainly in the plain";
let pattern = /ain/g;
let result = "";
while (pattern.test(text)==true) {
result += "Found at pos " + pattern.lastIndex + "<br>";
}
Try it Yourself »
Description
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
lastIndex is an ECMAScript1 (ES1) feature.
ES1 (JavaScript 1997) is fully supported in all browsers:
| Chrome | Edge | Firefox | Safari | Opera | IE |
| Yes | 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 |
