---
title: "double(forKey:)"
framework: foundation
role: symbol
role_heading: Instance Method
path: "foundation/nsubiquitouskeyvaluestore/double(forkey:)"
---

# double(forKey:)

Returns the double value associated with the specified key.

## Declaration

```swift
func double(forKey aKey: String) -> Double
```

## Parameters

- `aKey`: The key to retrieve from the iCloud key-value store.

## Return Value

Return Value The double value associated with aKey, or 0.0 if the key isn’t present.

## Discussion

Discussion This method automatically coerces certain types to their equivalent double values. The Boolean value true becomes 1.0 and false becomes 0.0. An integer becomes the equivalent double –– for example, 2 becomes 2.0. A string that contains a numerical value contains the equivalent double — for example, “123.4” becomes 123.4.

## See Also

### Getting values

- [bool(forKey:)](foundation/nsubiquitouskeyvaluestore/bool(forkey:).md)
- [longLong(forKey:)](foundation/nsubiquitouskeyvaluestore/longlong(forkey:).md)
- [string(forKey:)](foundation/nsubiquitouskeyvaluestore/string(forkey:).md)
- [data(forKey:)](foundation/nsubiquitouskeyvaluestore/data(forkey:).md)
- [object(forKey:)](foundation/nsubiquitouskeyvaluestore/object(forkey:).md)
- [array(forKey:)](foundation/nsubiquitouskeyvaluestore/array(forkey:).md)
- [dictionary(forKey:)](foundation/nsubiquitouskeyvaluestore/dictionary(forkey:).md)
- [dictionaryRepresentation](foundation/nsubiquitouskeyvaluestore/dictionaryrepresentation.md)