CSSGroupingRule: insertRule() method

The insertRule() method of the CSSGroupingRule interface adds a new CSS rule to a list of CSS rules.

Syntax

insertRule(rule)
insertRule(rule, index)

Parameters

rule

A string

index Optional

An optional index at which to insert the rule; defaults to 0.

Return value

The index of the new rule.

Exceptions

IndexSizeError DOMException

Thrown if index is greater than the number of child CSS rules.

HierarchyRequestError DOMException

Thrown if rule cannot be inserted at the specified index due to some CSS constraint.

HierarchyRequestError DOMException

Thrown if the rule is a valid statement but not a nested statement.

Examples

let myRules = document.styleSheets[0].cssRules;
myRules[0].insertRule(
  "html {background-color: blue;}",
  0,
); /* inserts a rule for the HTML element at position 0 */

Specifications

Browser compatibility