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# decodeCGAffineTransform(forKey:)

Decodes and returns the Core Graphics affine transform structure associated with the specified key in the coder’s archive.

```
func decodeCGAffineTransform(forKey key: String) -> CGAffineTransform
```

## Parameters

`key`

The key that identifies the affine transform.

## Return Value

The affine transform.

## Discussion

Use this method to decode size information that was previously encoded using the [`encode(_:forKey:)`](/documentation/Foundation/NSCoder/encode(_:forKey:)-29jyx) method.

## See Also

[`encode(_:forKey:)`](/documentation/Foundation/NSCoder/encode(_:forKey:)-29jyx)

Encodes an affine transform and associates it with the specified key in the receiver’s archive.


---

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