---
title: "index(forIdentifier:)"
framework: addressbook
role: symbol
role_heading: Instance Method
path: "addressbook/abmultivalue/index(foridentifier:)"
---

# index(forIdentifier:)

Returns the index for the given identifier.

## Declaration

```swift
func index(forIdentifier identifier: String!) -> Int
```

## Parameters

- `identifier`: The identifier whose index will be returned.

## Discussion

Discussion If the identifier is not found, returns NSNotFound.

## See Also

### Accessing identifiers

- [identifier(at:)](addressbook/abmultivalue/identifier(at:).md)