This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The substringData() method of the CharacterData interface returns a portion of the existing data, starting at the specified index and extending for a given number of characters afterwards.
substringData(offset, count)
offsetThe index of the first character to include in the returned substring. 0 is the first character of the string.
countThe number of characters to return.
A string with the substring.
IndexSizeError DOMException
Thrown if offset + count is larger than the length of the contained data.
| Specification |
|---|
| DOM> # dom-characterdata-substringdata> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
substringData |
1 | 12 | 1 | ≤12.1 | 1 | 18 | 4 | ≤12.1 | 1 | 1.0 | 4.4 | 1 |
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https://developer.mozilla.org/en-US/docs/Web/API/CharacterData/substringData