CSS Declaration Block
ACSS declaration block is an ordered collection of CSS properties and values. It is represented in the DOM as aCSSStyleDeclaration.
Each property and value pairing is known as aCSS declaration. The CSS declaration block has the following associated properties:
- computed flag
Set if the
CSSStyleDeclarationobject is a computed rather than specified style. Unset by default.- declarations
TheCSS declarations associated with this object.
- parent CSS rule
The
CSSRulethat the CSS declaration block is associated with, otherwise null.- owner node
The
elementthat the CSS declaration block is associated with, otherwise null.- updating flag
Set when the CSS declaration block is updating the owner node's
styleattribute.
When aCSSStyleDeclaration is returned by aCSS Object Model (CSSOM) interface these properties are set to appropriate values as defined by the specification.
Basic example
The following example shows a CSS rule with a declaration block for theh1 element. The CSS declaration block is the lines between the curly braces.
h1 { margin: 0 auto; font-family: "Helvetica Neue", "Arial", sans-serif; font-style: italic; color: rebeccapurple;}We can return aCSSStyleDeclaration representing this CSS declaration block usingCSSStyleRule.style.
let myRules = document.styleSheets[0].cssRules;let rule = myRules[0]; // a CSSStyleRuleconsole.log(rule.style); // a CSSStyleDeclaration objectSpecifications
| Specification |
|---|
| CSS Object Model (CSSOM) # css-declaration-blocks |