---
category: [Administration & Integrations, Platform and Product Extensions, Platform and Product Extensions/Integration, Administration & Integrations/Custom Integrations & Apps, Platform and Product Extensions/Workday Extend]
keyword: [Extend, PMD Scripting, Scripts]
nav: wcp_docs
parent_url: /wcp_docs/
title: containsKey (key)
layout: subsection
---

## <a id="section_m3p_myb_5db"></a>Description

Returns true if the map contains a mapping for the specified key. This function takes linear time.

## <a id="section_cyq_j1m_zsb"></a>Return Type

`boolean`

## <a id="section_dz5_pwg_5db"></a>Instance Method Syntax

```
thisMap.containsKey(key)
```

<table><thead><tr><th>Parameter</th><th>Description</th></tr></thead><tbody><tr><td>key</td><td>The key to find.</td></tr></tbody></table><br/>

<b>Example</b>

`{'bar':2, 'foo':1}.containsKey('bar')`

Returns `true`

## <a id="section_njs_xzl_zsb"></a>Namespace Function Syntax

```
map:containsKey(map, key)
```

<table><thead><tr><th>Parameter</th><th>Description</th></tr></thead><tbody><tr><td>map</td><td>The input Map.</td></tr><tr><td>key</td><td>The key to find.</td></tr></tbody></table><br/>