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# replaceBytes(in:withBytes:)

Replaces with a given set of bytes a given range within the contents of the receiver.

```
func replaceBytes(in range: NSRange, withBytes bytes: UnsafeRawPointer)
```

## Parameters

`range`

The range within the receiver’s contents to replace with `bytes`. The range must not exceed the bounds of the receiver.

`bytes`

The data to insert into the receiver’s contents.

## Discussion

If the location of `range` isn’t within the receiver’s range of bytes, an `NSRangeException` is raised. The receiver is resized to accommodate the new bytes, if necessary.

A sample using this method is given in [Working With Mutable Binary Data](https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/BinaryData/Tasks/WorkingMutableData.html#//apple_ref/doc/uid/20002150).

---

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