# string(at:effectiveRange:endsWithSearchBoundary:) Returns the found string that is created by conceptually mapping its content to a single string, which is composed of a concatenation of all its substrings. ``` optional func string(at characterIndex: Int, effectiveRange outRange: NSRangePointer, endsWithSearchBoundary outFlag: UnsafeMutablePointer) -> String ``` ## Parameters `characterIndex` The given character index the client should return. `outRange` Returns, by reference, the “effective range” of that substring in the full conceptually concatenated string `outFlag` Returns, by-reference, whether the substring ends with a “search boundary”, meaning that NSTextFinder should not attempt to find any matches that overlap this boundary. ## Return Value Returns the found string. ## Discussion See [`NSTextFinder`](/documentation/AppKit/NSTextFinder) for more information. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)