# addOfItem(at:withContentsOf:options:) Creates a version of the file at the specified location. ``` class func addOfItem(at url: URL, withContentsOf contentsURL: URL, options: NSFileVersion.AddingOptions = []) throws -> NSFileVersion ``` ## Parameters `url` The location at which to store the new file version. `contentsURL` The URL that specifies the file to use for the version contents. `options` Specify 0 for this parameter if you want to create a copy of the file at the location specified by the `url` parameter. Alternatively, specify one of the constants described in [`NSFileVersion.AddingOptions`](/documentation/Foundation/NSFileVersion/AddingOptions). ## Return Value The file version object representing the new version or `nil` if an error occurred. ## Discussion You can use this method to save a version of your file to the location specified by the `url` parameter. The contents of the file are taken from the `contentsURL` parameter, whose value may be the same as the `url` parameter. You should always add file versions as part of a coordinated write operation to a file. In other words, always call this method from a block passed to a file coordinator object to initiate a write operation. Doing so ensures that no other processes are operating on the file while you save the version to its new location. > Handling Errors in Swift: > In Swift, this method returns a nonoptional result and is marked with the `throws` keyword to indicate that it throws an error in cases of failure. > > You call this method in a `try` expression and handle any errors in the `catch` clauses of a `do` statement, as described in [Error Handling](https://docs.swift.org/swift-book/LanguageGuide/ErrorHandling.html) in [The Swift Programming Language](https://docs.swift.org/swift-book/) and `About Imported Cocoa Error Parameters`. --- 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)