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# CFDictionaryContainsKey(_:_:)

Returns a Boolean value that indicates whether a given key is in a dictionary.

```
func CFDictionaryContainsKey(_ theDict: CFDictionary!, _ key: UnsafeRawPointer!) -> Bool
```

## Parameters

`theDict`

The dictionary to examine.

`key`

The key for which to find matches in `theDict`. The key hash and equal callbacks provided when the dictionary was created, are used to compare. If the hash callback is `NULL`, `key` is treated as a pointer and converted to an integer. If the equal callback is `NULL`, pointer equality (in C, ==) is used. If `key`, or any of the keys in the dictionary, is not understood by the equal callback, the behavior is undefined.

## Return Value

`true` if `key` is in the dictionary, otherwise `false`.

## Discussion

---

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