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# init(base64Encoding:)

Initializes a data object initialized with the given Base64 encoded string.

```
init?(base64Encoding base64String: String)
```

## Parameters

`base64String`

A Base-64 encoded string.

## Return Value

A data object built by Base-64 decoding the provided string. Returns `nil` if the data object could not be decoded.

## Discussion

Although this method was only introduced publicly for iOS 7, it has existed since iOS 4; you can use it if your application needs to target an operating system prior to iOS 7. This method behaves like [`init(base64EncodedString:options:)`](/documentation/Foundation/NSData/init(base64EncodedString:options:)), but ignores all unknown characters.

---

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