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web api instance method

CSSFontFeatureValuesMap: forEach() method

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Limited availability

The forEach() method of CSSFontFeatureValuesMap instances executes a provided function once per each key/value pair in this map, in insertion order.

Syntax

forEach(callbackFn)
forEach(callbackFn, thisArg)

Parameters

  • callbackFn
    • : A function to execute for each entry in the map. The function is called with the following arguments:
      • value
        • : Value of each iteration.
      • key
        • : Key of each iteration.
      • map
        • : The map being iterated.
  • thisArg Optional
    • : A value to use as this when executing callbackFn.

Return value

None (undefined).

Examples

Basic usage

The following example logs the key and value for each entry in the @swash rule. This example is using @swash but also works with other feature value blocks.

CSS

@font-feature-values "MonteCarlo" {
  @swash {
    swishy: 1;
    swashy: 2;
  }
}

JavaScript

// function to be used as callback
function logSwashes(value, key, map) {
  console.log(`('${key}') = ${value}`);
}
// get the rules
const myRule = document.styleSheets[0].cssRules[0];
myRule.swash.forEach(logSwashes);
// logs:
// "('swishy') = 1"
// "('swashy') = 2"

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also