Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.
Non-standard: This feature is not standardized. We do not recommend using non-standard features in production, as they have limited browser support, and may change or be removed. However, they can be a suitable alternative in specific cases where no standard option exists.
The cssValueType read-only property of the CSSValue interface represents the type of the current computed CSS property value.
Note: This property was part of an attempt to create a typed CSS Object Model. This attempt has been abandoned, and most browsers do not implement it.
To achieve your purpose, you can use:
An unsigned short representing a code defining the type of the value. Possible values are:Constant Description CSS_CUSTOMThe value is a custom value. CSS_INHERITThe value is inherited and the cssText contains "inherit".CSS_PRIMITIVE_VALUEThe value is a primitive value and an instance of the CSSPrimitiveValue interface can be obtained by using binding-specific casting methods on this instance of the CSSValue interface.CSS_VALUE_LISTThe value is a CSSValue list and an instance of the CSSValueList interface can be obtained by using binding-specific casting methods on this instance of the CSSValue interface.
const styleDeclaration = document.styleSheets[0].cssRules[0].style;
const cssValue = styleDeclaration.getPropertyCSSValue("color");
console.log(cssValue.cssValueType);This feature was originally defined in the DOM Style Level 2 specification, but has been dropped from any standardization effort since then.
It has been superseded by a modern, but incompatible, CSS Typed Object Model API that is now on the standard track.