# Class Map - [TopLevel.Object](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md) - [TopLevel.Map](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Map.md) Map objects are collections of key/value pairs where both the keys and values may be arbitrary ECMAScript language values. A distinct key value may only occur in one key/value pair within the Map's collection. Key/value pairs are stored and iterated in insertion order. **API Version:** :::note Available from version 21.2. ::: ## Property Summary | Property | Description | | ------------------------------------------------------------------------------------------------- | --------------------------------------------- | | [size](#size): [Number](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Number.md) | Number of key/value pairs stored in this map. | ## Constructor Summary | Constructor | Description | | ----------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------- | | [Map](#map)() | Creates an empty map. | | [Map](#mapiterable)([Iterable](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Iterable.md)) | If the passed value is null or undefined then an empty map is constructed. | ## Method Summary | Method | Description | | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------- | | [clear](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Map.md#clear)() | Removes all key/value pairs from this map. | | [delete](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Map.md#deleteobject)([Object](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md)) | Removes the entry for the given key. | | [entries](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Map.md#entries)() | Returns an iterator containing all key/value pairs of this map. | | [forEach](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Map.md#foreachfunction)([Function](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Function.md)) | Runs the provided callback function once for each key/value pair present in this map. | | [forEach](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Map.md#foreachfunction-object)([Function](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Function.md), [Object](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md)) | Runs the provided callback function once for each key/value pair present in this map. | | [get](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Map.md#getobject)([Object](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md)) | Returns the value associated with the given key. | | [has](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Map.md#hasobject)([Object](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md)) | Returns if this map has value associated with the given key. | | [keys](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Map.md#keys)() | Returns an iterator containing all keys of this map. | | [set](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Map.md#setobject-object)([Object](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md), [Object](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md)) | Adds or updates a key/value pair to the map. | | [values](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Map.md#values)() | Returns an iterator containing all values of this map. | ### Methods inherited from class Object [assign](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#assignobject-object), [create](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#createobject), [create](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#createobject-object), [defineProperties](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#definepropertiesobject-object), [defineProperty](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#definepropertyobject-object-object), [entries](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#entriesobject), [freeze](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#freezeobject), [fromEntries](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#fromentriesiterable), [getOwnPropertyDescriptor](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#getownpropertydescriptorobject-object), [getOwnPropertyNames](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#getownpropertynamesobject), [getOwnPropertySymbols](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#getownpropertysymbolsobject), [getPrototypeOf](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#getprototypeofobject), [hasOwnProperty](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#hasownpropertystring), [is](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#isobject-object), [isExtensible](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#isextensibleobject), [isFrozen](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#isfrozenobject), [isPrototypeOf](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#isprototypeofobject), [isSealed](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#issealedobject), [keys](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#keysobject), [preventExtensions](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#preventextensionsobject), [propertyIsEnumerable](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#propertyisenumerablestring), [seal](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#sealobject), [setPrototypeOf](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#setprototypeofobject-object), [toLocaleString](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#tolocalestring), [toString](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#tostring), [valueOf](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#valueof), [values](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md#valuesobject) ## Property Details ### size - size: [Number](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Number.md) - : Number of key/value pairs stored in this map. *** ## Constructor Details ### Map() - Map() - : Creates an empty map. *** ### Map(Iterable) - Map(values: [Iterable](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Iterable.md)) - : If the passed value is null or undefined then an empty map is constructed. Else an iterator object is expected that produces a two element array-like object whose first element is a value that will be used as a Map key and whose second element is the value to associate with that key. **Parameters:** - values - The initial map values *** ## Method Details ### clear() - clear(): void - : Removes all key/value pairs from this map. *** ### delete(Object) - delete(key: [Object](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md)): [Boolean](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Boolean.md) - : Removes the entry for the given key. **Parameters:** - key - The key of the key/value pair to be removed from the map. **Returns:** - `true` if the map contained an entry for the passed key that was removed. Else `false` is returned. *** ### entries() - entries(): [ES6Iterator](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.ES6Iterator.md) - : Returns an iterator containing all key/value pairs of this map. The iterator produces a series of two-element arrays with the first element as the key and the second element as the value. *** ### forEach(Function) - forEach(callback: [Function](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Function.md)): void - : Runs the provided callback function once for each key/value pair present in this map. **Parameters:** - callback - The function to call, which is invoked with three arguments: the value of the element, the key of the element, and the Map object being iterated. *** ### forEach(Function, Object) - forEach(callback: [Function](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Function.md), thisObject: [Object](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md)): void - : Runs the provided callback function once for each key/value pair present in this map. **Parameters:** - callback - The function to call, which is invoked with three arguments: the value of the element, the key of the element, and the Map object being iterated. - thisObject - The Object to use as 'this' when executing callback. *** ### get(Object) - get(key: [Object](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md)): [Object](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md) - : Returns the value associated with the given key. **Parameters:** - key - The key to look for. **Returns:** - The value associated with the given key if an entry with the key exists else `undefined` is returned. *** ### has(Object) - has(key: [Object](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md)): [Boolean](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Boolean.md) - : Returns if this map has value associated with the given key. **Parameters:** - key - The key to look for. **Returns:** - `true` if an entry with the key exists else `false` is returned. *** ### keys() - keys(): [ES6Iterator](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.ES6Iterator.md) - : Returns an iterator containing all keys of this map. *** ### set(Object, Object) - set(key: [Object](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md), value: [Object](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md)): [Map](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Map.md) - : Adds or updates a key/value pair to the map. You can't use JavaScript bracket notation to access map entries. JavaScript bracket notation accesses only properties for Map objects, not map entries. **Parameters:** - key - The key object. - value - The value to be associated with the key. **Returns:** - This map object. *** ### values() - values(): [ES6Iterator](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.ES6Iterator.md) - : Returns an iterator containing all values of this map. ***