This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The insertItemBefore() method of the SVGLengthList interface inserts a new item into the list at the specified position. The first item is indexed 0. The inserted item is the item itself and not a copy.
length, then the new item is appended to the end of the list.insertItemBefore(newItem, index)
newItemThe SVGLength to add to the list.
indexA non-negative integer that specifies the index of the item to insert the new item before.
The SVGLength that was added to the list.
NoModificationAllowedError DOMException
Thrown when the list is read-only.
See SVGLengthList for a complete example.
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
insertItemBefore |
1 | 12 | 1.5 | ≤12.1 | 3 | 18 | 4 | ≤12.1 | 1 | 1.0 | 3 | 1 |
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https://developer.mozilla.org/en-US/docs/Web/API/SVGLengthList/insertItemBefore