# load(fromContents:ofType:) Loads the document data into the app’s data model. ``` func load(fromContents contents: Any, ofType typeName: String?) throws ``` ## Parameters `contents` An object encapsulating the document data to load. This object is either an instance of the class (for flat files) or the class (for file packages). `typeName` The file type of the document, a Uniform Type Identifier (UTI) based on the file extension of [`fileURL`](/documentation/UIKit/UIDocument/fileURL). You can obtain the default value of the file type from the [`fileType`](/documentation/UIKit/UIDocument/fileType) property. ## Discussion Override this method to accept and load the data for a document. After `UIDocument` reads the document data from the file located at [`fileURL`](/documentation/UIKit/UIDocument/fileURL) it calls your subclass, passing the data to the subclass in this method. This method is called on the queue that the [`open(completionHandler:)`](/documentation/UIKit/UIDocument/open(completionHandler:)) method was called on (typically, the main queue). > Handling Errors in Swift: > In Swift, this method is marked with the `throws` keyword to indicate that it throws an error in cases of failure. > > When overriding this method, use the `throw` statement to throw an `NSError`, 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)