NSAttributedStringMBS.NSTopMarginDocumentAttribute as string

Number, containing a float, in points.
Mac OS X v10.3 and earlier string constant is "TopMargin".
Available in Mac OS X v10.4 and later.

NSAttributedStringMBS.NSUnderlineColorAttributeName as string

NSColor
Default nil, same as foreground color
Available in Mac OS X v10.3 and later.

NSAttributedStringMBS.NSUnderlineStyleAttributeName as string

Number containing integer
Default 0, no underline. See "Underlining Patterns", "Underlining Styles", and "Underline Masks" in Apple Documentation for mask values.

NSAttributedStringMBS.NSVerticalGlyphFormAttributeName as string

An Number containing an integer value, 0 means horizontal text and 1 indicates vertical text. If no value specified, it's interpreted to determine the setting based on higher-level vertical orientation settings such as NSTextLayoutOrientation . The behavior for any other value is undefined.
Available in Mac OS X v10.7 and later.

NSAttributedStringMBS.NSViewModeDocumentAttribute as string

NSValue, containing an int; 0 = normal; 1 = page layout (use value of "PaperSize").
Mac OS X v10.3 and earlier string constant is "ViewMode".
Available in Mac OS X v10.4 and later.

NSAttributedStringMBS.NSViewSizeDocumentAttribute as string

NSValue, containing NSSize.
Mac OS X v10.3 and earlier string constant is "ViewSize".
Available in Mac OS X v10.4 and later.

NSAttributedStringMBS.NSViewZoomDocumentAttribute as string

Mac OS X v10.3 and earlier string constant is "ViewZoom".
NSValue, containing a float; 100 = 100% zoom.
Available in Mac OS X v10.4 and later.

NSAttributedStringMBS.NSWebArchiveTextDocumentType as string

Web Kit WebArchive document.

NSAttributedStringMBS.NSWebPreferencesDocumentOption as string

WebPreferences; for HTML only, specifies a WebPreferences object. If not present, a default set of preferences is used. Previous string constant was @"WebPreferences".
Available in Mac OS X v10.4 and later.

NSAttributedStringMBS.NSWebResourceLoadDelegateDocumentOption as string

WebResourceLoadDelegateMBS; for HTML only, specifies an object to serve as the web resource loading delegate.
If not present, a default delegate is used that permits the loading of subsidiary resources but does not respond to authentication challenges. Previous string constant was @"WebResourceLoadDelegate".
Available in Mac OS X v10.4 and later.

NSAttributedStringMBS.NSWordMLTextDocumentType as string

Microsoft Word XML (WordML schema) document.

NSAttributedStringMBS.NSWritingDirectionAttributeName as string

const NSWritingDirectionNatural       = -1   // Determines direction using the Unicode Bidi Algorithm rules P2 and P3
const NSWritingDirectionLeftToRight   = 0    // Left to right writing direction
const NSWritingDirectionRightToLeft   = 1    // Right to left writing direction

const NSTextWritingDirectionEmbedding = 0
const NSTextWritingDirectionOverride = 2

dim t as NSTextStorageMBS = TextArea1.NSTextViewMBS.textStorage

// get hello in arabic
dim a as NSAttributedStringMBS = NSAttributedStringMBS.attributedStringWithString("مرحبا")
dim m as NSMutableAttributedStringMBS = a.mutableCopy

// now set attributes for right to left
m.addAttribute t.NSWritingDirectionAttributeName, array(NSWritingDirectionRightToLeft+NSTextWritingDirectionOverride), new NSRangeMBS(0,m.Length)

// and add to textarea
t.appendAttributedString m

An Array of Numbers.
This provides a means to override the default bidi algorithm, equivalent to the use of bidi control characters LRE, RLE, LRO, or RLO paired with PDF, as a higher-level attribute. This is the NSAttributedString equivalent of HTML's dir attribute and/or BDO element. The array represents nested embeddings or overrides, in order from outermost to innermost. The values of the Numbers should be 0, 1, 2, or 3, for LRE, RLE, LRO, or RLO respectively; these should be regarded as NSWritingDirectionLeftToRight or NSWritingDirectionRightToLeft plus NSTextWritingDirectionEmbedding or NSTextWritingDirectionOverride.
Available in Mac OS X v10.6 and later.