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SVGTextContentElement: getSubStringLength() method

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨July 2015⁩.

The getSubStringLength() method of the SVGTextContentElement interface represents the computed length of the formatted text advance distance for a substring of text within the element.

Note that this method only accounts for the widths of the glyphs in the substring and any extra spacing inserted by the CSS letter-spacing and word-spacing properties. Visual spacing adjustments made by the x attribute are ignored.

Syntax

getSubStringLength(index, length)

Parameters

index

An integer; the start index of the substring.

length

An integer; the number of characters to include in the substring.

Return value

A float.

Exceptions

IndexSizeError DOMException

Thrown if the index is greater than the highest index or length is negative.

Examples

>

Getting the Length of a Substring

<svg width="300" height="100">
  <text id="exampleText" x="10" y="50" font-size="16">Hello, SVG World!</text>
</svg>
const textElement = document.getElementById("exampleText");

// Get the length of a substring starting at character 0 with 5 characters
const substringLength = textElement.getSubStringLength(0, 5);

console.log(substringLength); // Output: 35.55

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Opera Safari Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet WebView Android WebView on iOS
getSubStringLength 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/SVGTextContentElement/getSubStringLength