# Class MappingKey

- [TopLevel.Object](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.Object.md)
  - [dw.util.MappingKey](/docs/commerce/b2c-commerce/references/b2c-script-api/dw.util.MappingKey.md)

Encapsulates the key for a mapping read in with the ImportKeyValueMapping job step. Can be either single or compound keys. For example, a
single string (e.g. product id) or multiple string components (e.g. product id and site).

## Property Summary

| Property                                                                                                                                    | Description                                                |
| ------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------- |
| [keyComponents](#keycomponents): [String\[\]](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.String.md) `(read-only)`       | Gets the (possible compound) key.                          |
| [singleComponentKey](#singlecomponentkey): [String](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.String.md) `(read-only)` | Gets a key that contains only a single key component (i.e. |

## Constructor Summary

| Constructor                                                                                                            | Description                                           |
| ---------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------- |
| [MappingKey](#mappingkeystring)([String...](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.String.md)) | Instantiates a new key using compound key components. |

## Method Summary

| Method                                                                                                                       | Description                                                |
| ---------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------- |
| [getKeyComponents](/docs/commerce/b2c-commerce/references/b2c-script-api/dw.util.MappingKey.md#getkeycomponents)()           | Gets the (possible compound) key.                          |
| [getSingleComponentKey](/docs/commerce/b2c-commerce/references/b2c-script-api/dw.util.MappingKey.md#getsinglecomponentkey)() | Gets a key that contains only a single key component (i.e. |

### 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

### keyComponents

- keyComponents: [String\[\]](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.String.md) `(read-only)`
  - : Gets the (possible compound) key. If the key consists of only of a single value, the string array
    will simply contain a single element.

***

### singleComponentKey

- singleComponentKey: [String](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.String.md) `(read-only)`
  - : Gets a key that contains only a single key component (i.e. that is not a compound key). Returns null if this is
    not a single component key.

***

## Constructor Details

### MappingKey(String...)

- MappingKey(keyComponents: [String...](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.String.md))
  - : Instantiates a new key using compound key components. A key can consist of a single string (e.g. product id) or
    multiple string components (e.g. product id and site). Ctor accepts single string or multiple components for a
    compound key.

    **Parameters:**

    - keyComponents - the key components

***

## Method Details

### getKeyComponents()

- getKeyComponents(): [String\[\]](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.String.md)
  - : Gets the (possible compound) key. If the key consists of only of a single value, the string array
    will simply contain a single element.

    **Returns:**

    - the key

***

### getSingleComponentKey()

- getSingleComponentKey(): [String](/docs/commerce/b2c-commerce/references/b2c-script-api/TopLevel.String.md)
  - : Gets a key that contains only a single key component (i.e. that is not a compound key). Returns null if this is
    not a single component key.

    **Returns:**

    - the single key

***