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web api interface

CSSPageRule

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CSSPageRule represents a single CSS @page rule.

Instance properties

Inherits properties from its ancestors CSSGroupingRule and CSSRule.

Instance methods

Inherits methods from its ancestors CSSGroupingRule and CSSRule.

Examples

Filtering for page rules

This example shows how you can find CSSPageRule objects for @page rules loaded by the document.

<pre id="log"></pre>
const logElement = document.querySelector("#log");
function log(text) {
  logElement.innerText = `${logElement.innerText}${text}\n`;
  logElement.scrollTop = logElement.scrollHeight;
}
#log {
  height: 220px;
  overflow: scroll;
  padding: 0.5rem;
  border: 1px solid black;
}

CSS

Below we define styles for the page using a @page rule.

@page {
  margin: 1cm;
}

JavaScript

The code iterates through all the sheets in the document, and through all the cssRules in each sheet, logging the sheet index, the number of rules, and the type of each rule object. We then detect CSSPageRule objects using their type (doing nothing with the information).

for (
  let sheetCount = 0;
  sheetCount < document.styleSheets.length;
  sheetCount++
) {
  const sheet = document.styleSheets[sheetCount].cssRules;
  log(`styleSheet: ${sheetCount}`);

  const myRules = document.styleSheets[sheetCount].cssRules;
  log(`rules: ${myRules.length}`);
  for (const rule of myRules) {
    log(`rule: ${rule}`);
    if (rule instanceof CSSPageRule) {
      // Do something with CSSPageRule
    }
  }
}

Results

The results are shown below. As you can see there are a two sheets, corresponding to this main document and the example code frame, and each have a number of rules, only one of which is our CSSPageRule.

Interactive exampleOpen the canonical MDN source to run this embedded demo.

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.