您必须将转换NSMutableAttributedString为，NSData然后将其存储在中NSUserDefaults。

    // Convert into NSData
    let data = NSKeyedArchiver.archivedDataWithRootObject(distanceMutableAttributedString)
    NSUserDefaults.standardUserDefaults().setObject(data, forKey: "yourStringIntoData")

    // Convert your NSData to NSMutableAttributedString
    let yourStringInData = NSUserDefaults.standardUserDefaults().objectForKey("yourStringIntoData") as? NSData
    let newStr = NSKeyedUnarchiver.unarchiveObjectWithData(yourStringInData!) as? NSMutableAttributedString

   // Assign it to your textView
    textView.attributedText = newStr