CSSKeyframesRule

{{APIRef("CSSOM")}}

The CSSKeyframesRule interface describes an object representing a complete set of keyframes for a CSS animation. It corresponds to the contents of a whole {{cssxref("@keyframes")}} at-rule.

{{InheritanceDiagram}}

Instance properties

Inherits properties from its ancestor {{domxref("CSSRule")}}.

• {{domxref("CSSKeyframesRule.name")}}
  • : Represents the name of the keyframes, used by the {{cssxref("animation-name")}} property.
• {{domxref("CSSKeyframesRule.cssRules")}} {{ReadOnlyInline}}
  • : Returns a {{domxref("CSSRuleList")}} of the keyframes in the list.
• {{domxref("CSSKeyframesRule.length")}} {{ReadOnlyInline}}
  • : Returns the number of keyframes in the list.

Instance methods

Inherits methods from its ancestor {{domxref("CSSRule")}}.

• {{domxref("CSSKeyframesRule.appendRule()")}}
  • : Inserts a new keyframe rule into the current CSSKeyframesRule. The parameter is a string containing a keyframe in the same format as an entry of a {{cssxref("@keyframes")}} at-rule. If it contains more than one keyframe rule, a {{domxref("DOMException")}} with a SYNTAX_ERR is thrown.
• {{domxref("CSSKeyframesRule.deleteRule()")}}
  • : Deletes a keyframe rule from the current CSSKeyframesRule. The parameter is the index of the keyframe to be deleted, expressed as a string resolving as a number between 0% and 100%.
• {{domxref("CSSKeyframesRule.findRule()")}}
  • : Returns a keyframe rule corresponding to the given key. The key is a string containing an index of the keyframe to be returned, resolving to a percentage between 0% and 100%. If no such keyframe exists, findRule returns null.

Example

Using CSSKeyframesRule

The CSS includes a keyframes at-rule. This will be the first {{domxref("CSSRule")}} returned by document.styleSheets[0].cssRules. myRules[0] returns a CSSKeyframesRule object.

@keyframes slide-in {
  from {
    transform: translateX(0%);
  }

  to {
    transform: translateX(100%);
  }
}

const myRules = document.styleSheets[0].cssRules;
const keyframes = myRules[0]; // a CSSKeyframesRule

Accessing indexes

CSSKeyframesRule can be indexed like an array, and functions similar to its {{domxref("CSSKeyframesRule.cssRules", "cssRules")}} property.

const keyframes = document.styleSheets[0].cssRules[0];

for (let i = 0; i < keyframes.length; i++) {
  console.log(keyframes[i].keyText);
}

// Output:
// 0%
// 100%

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• {{cssxref("@keyframes")}}
• {{domxref("CSSKeyFrameRule")}}