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# decodeInt64(forKey:)

Decodes a 64-bit integer value associated with a given key.

```
func decodeInt64(forKey key: String) -> Int64
```

## Parameters

`key`

A key in the archive within the current decoding scope. `key` must not be `nil`.

## Return Value

The 64-bit integer value associated with the key `key`. Returns `0` if `key` does not exist.

## Discussion

If the archived value was encoded with a different size but is still an integer, the type is coerced.

## See Also

[`encode(_:forKey:)`](/documentation/Foundation/NSKeyedArchiver/encode(_:forKey:)-ycdd)

Encodes a given 64-bit integer value and associates it with a key.


---

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