Function getEffectiveStyle

javascript/atoms/typescript/is-displayed.ts:90–102

(elem: Element, propertyName: string)

  }

  function getEffectiveStyle(elem: Element, propertyName: string): string | null {
    var computed = computedStyleCache.get(elem);
    if (computed === undefined) {
      var win = elem.ownerDocument.defaultView;
      computed = win ? (win.getComputedStyle(elem) || null) : null;
      computedStyleCache.set(elem, computed);
    }
    if (!computed) {
      return null;
    }
    var value = computed.getPropertyValue(propertyName);
    return value || null;
  }

  function getOpacity(elem: Element): number {
    var opacityStyle = getEffectiveStyle(elem, 'opacity');