The ignoreCase
accessor property indicates whether or not the i
flag is used with the regular expression.
The ignoreCase
accessor property indicates whether or not the i
flag is used with the regular expression.
RegExp.prototype.ignoreCase
has the value true
if the i
flag was used; otherwise, false
. The i
flag indicates that case should be ignored while attempting a match in a string.
If the regex has the unicode
flag, the case mapping happens as specified in CaseFolding.txt
. Otherwise, case mapping uses the Unicode Default Case Conversion — the same algorithm used in String.prototype.toUpperCase()
and String.prototype.toLowerCase()
.
The set accessor of ignoreCase
is undefined
. You cannot change this property directly.
const regex = /foo/i; console.log(regex.ignoreCase); // true
Desktop | Mobile | Server | ||||||||||||
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Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | WebView Android | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | Deno | Node.js | |
ignoreCase |
1 |
12 |
1 |
5.5 |
5 |
1 |
4.4 |
18 |
4 |
10.1 |
1 |
1.0 |
1.0 |
0.10.0 |
prototype_accessor |
48 |
12 |
38 |
5.5 |
35 |
1.3 |
48 |
48 |
38 |
35 |
1 |
5.0 |
1.0 |
6.0.0 |
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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/ignoreCase