# Document reading option keys Keys for constructing an attributed string from data on disk. ## Overview Use these keys when you need to specify a key of type [`NSAttributedStringDocumentReadingOptionKey`](/documentation/UIKit/NSAttributedStringDocumentReadingOptionKey). ## Topics ### Getting the document options [`extern NSAttributedStringDocumentReadingOptionKey const NSCharacterEncodingDocumentOption;`](/documentation/UIKit/NSCharacterEncodingDocumentOption) The string encoding. [`extern NSAttributedStringDocumentReadingOptionKey const NSDefaultAttributesDocumentOption;`](/documentation/UIKit/NSDefaultAttributesDocumentOption) [`extern NSAttributedStringDocumentReadingOptionKey const NSDocumentTypeDocumentOption;`](/documentation/UIKit/NSDocumentTypeDocumentOption) The document type. ### Getting the font-scaling options [`extern NSAttributedStringDocumentReadingOptionKey const NSSourceTextScalingDocumentOption;`](/documentation/UIKit/NSSourceTextScalingDocumentOption) The text-scaling mode to associate with the document’s content. [`extern NSAttributedStringDocumentReadingOptionKey const NSTargetTextScalingDocumentOption;`](/documentation/UIKit/NSTargetTextScalingDocumentOption) The text scaling mode to use after reading the text from disk. ### Getting the key type [`typedef NSString * NSAttributedStringDocumentReadingOptionKey;`](/documentation/UIKit/NSAttributedStringDocumentReadingOptionKey) Options for constructing an attributed string from data you read from disk. ### Getting list marker format options [`extern NSAttributedStringDocumentReadingOptionKey const NSTextKit1ListMarkerFormatDocumentOption;`](/documentation/UIKit/NSTextKit1ListMarkerFormatDocumentOption) --- 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)