---
title: "init(keyName:searchable:searchableByDefault:unique:multiValued:)"
framework: corespotlight
role: symbol
role_heading: Initializer
path: "corespotlight/cscustomattributekey/init(keyname:searchable:searchablebydefault:unique:multivalued:)"
---

# init(keyName:searchable:searchableByDefault:unique:multiValued:)

Returns a new custom attribute key with the specified name and properties.

## Declaration

```swift
init?(keyName: String, searchable: Bool, searchableByDefault: Bool, unique: Bool, multiValued: Bool)
```

## Parameters

- `keyName`: The name of the custom attribute for use as a key in a doc://com.apple.corespotlight/documentation/CoreSpotlight/CSSearchableItemAttributeSet. The key name must be a string that contains only ASCII characters and no punctuation other than the underscore (that is, “_”). The prefix kMD is reserved.
- `searchable`: A Boolean value that indicates if the attribute can be specified as a search term.
- `searchableByDefault`: A Boolean value that indicates if the attribute should be searchable by default.
- `unique`: A Boolean value that indicates if duplicate values should be treated as the same value to save storage space.
- `multiValued`: A Boolean value that indicates if the attribute is likely to have multiple values, such as arrays, associated with it.

## Return Value

Return Value A new custom attribute key with the specified name and properties.

## Discussion

Discussion To create custom attribute key names, it’s recommended that you use a reverse DNS format that includes your company name and does not include the period character (”.”). For example, a key name of the form com_mycompany_myapp_mykeyname works well.

## See Also

### Creating a custom attribute

- [init(keyName:)](corespotlight/cscustomattributekey/init(keyname:).md)
- [init(coder:)](corespotlight/cscustomattributekey/init(coder:).md)