CSSKeyframesRule.appendRule()

The appendRule() method of the CSSKeyframeRule interface appends a CSSKeyFrameRule to the end of the rules.

Syntax

CSSKeyframesRule.appendRule(rule);

Parameters

rule
A CSSOMString containing a keyframe rule.

Return value

None.

Example

The CSS includes a keyframes at-rule. This will be the first CSSRule returned by document.styleSheets[0].cssRules. myRules[0] returns a CSSKeyframesRule object. Returning the cssRules property would return a CSSRuleList containing one rule.

After appending another rule with appendRule the cssRules property returns a CSSRuleList containing two rules.

@keyframes slidein {
  from {
    transform: translateX(0%);
  }
}
let myRules = document.styleSheets[0].cssRules;
let keyframes = myRules[0]; // a CSSKeyframesRule
keyframes.appendRule('to {transform: translateX(100%);}');
console.log(keyframes.cssRules); // a CSSRuleList object with two rules

Specifications

Specification Status Comment
CSS Animations Level 1
The definition of 'CSSKeyframesRule.appendRule' in that specification.
Working Draft Initial definition

Browser compatibility

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