One Hand Typing

Uncategorized No Comments

If you have to type with one hand, AutoHotkey is a free option to turn your regular keyboard into a half mirror keyboard, where each key on one side is mirrored to the other (activate it by pressing Space key first).

Here’s a script, copied from AutoHotkey forum with slight modifications:

#SingleInstance, force
; Half-QWERTY: One-handed Typing - version 3a
; http://www.autohotkey.com/forum/viewtopic.php?p=228783#228783
;
; HalfKeyboard invented by Matias Corporation between 1992 and 1996
; Originally coded in AutoHotkey by jonny in 2004
; Many thanks to Chris for helping him out with this script.
; Capslock hacks and `~ remap to '" by Watcher
; This implementation was done by mbirth in 2007
;
; version 3a script, mod by hugov:
; 2008-10-31:
; - mixed with "Capitalize letters after 1 second hold" at request of Calibran
; http://www.autohotkey.com/forum/post-228311.html#228311
; just tested very briefly so try at your own peril :-)
;

KeyIsDown = 0
UpperDelay = 300
UpperDelay *= -1

RegRead KLang, HKEY_CURRENT_USER, Keyboard Layout\Preload, 1
StringRight KLang, KLang, 4
If (!KLang)
KLang := A_Language

If (KLang = "0407") {
; 0407 DE_de QWERTZ mirror set
original := "^12345qwertasdfgyxcvb"
mirrored := "ß09876poiuzölkjh-.,mn"
} Else If (KLang = "040c" || KLang = "040C") {
; 040c FR_fr AZERTY mirror set
original := "²&é" . """" . "'(azertqsdfgwxcvb" ; split up string for better
mirrored := ")àç" . "_" . "è-poiuymlkjh!:;,n" ; human readability
} Else {
; 0409 US_us QWERTY mirror set
original := "``" . "12345qwertasdfgzxcvb" ; split up string for better
mirrored := "'" . "09876poiuy;lkjh/.,mn" ; human readability
}

; Now define all hotkeys
Loop % StrLen(original)
{
c1 := SubStr(original, A_Index, 1)
c2 := SubStr(mirrored, A_Index, 1)
Hotkey Space & %c1%, DoHotkey
Hotkey Space & %c2%, DoHotkey
Hotkey %c1%, KeyDown
Hotkey %c1% UP, KeyUP
Hotkey %c2%, KeyDown ;
Hotkey %c2% UP, KeyUP ;
}

return

; This key may help, as the space-on-up may get annoying, especially if you type fast.
Control & Space::Suspend

; Not exactly mirror but as close as we can get, Capslock enter, Tab backspace.
Space & CapsLock::Send {Enter}
Space & Tab::Send {Backspace}

; If spacebar didn't modify anything, send a real space keystroke upon release.
+Space::Send {Space}
Space::Send {Space}

; General purpose
DoHotkey:
StartTime := A_TickCount
StringRight ThisKey, A_ThisHotkey, 1
i1 := InStr(original, ThisKey)
i2 := InStr(mirrored, ThisKey)
If (i1+i2 = 0) {
MirrorKey := ThisKey
} Else If (i1 > 0) {
MirrorKey := SubStr(mirrored, i1, 1)
} Else {
MirrorKey := SubStr(original, i2, 1)
}

Modifiers := ""
If (GetKeyState("LWin") || GetKeyState("RWin")) {
Modifiers .= "#"
}
If (GetKeyState("Control")) {
Modifiers .= "^"
}
If (GetKeyState("Alt")) {
Modifiers .= "!"
}
If (GetKeyState("Shift") + GetKeyState("CapsLock", "T") = 1) {
; only add if Shift is held OR CapsLock is on (XOR) (both held down would result in value of 2)
Modifiers .= "+"
}

If (KeyIsDown < 1 or ThisKey <> LastKey)
{
KeyIsDown := True
LastKey := ThisKey
Send %Modifiers%{%MirrorKey%}
SetKeyDelay, 65535
SetTimer, ReplaceWithUpperMirror, %UpperDelay%
}

Return

MenuShowKeyboardLayout:
IfWinNotExist, HalfKeyboard - permanent keyboard layout
{
Gui, +Owner +Toolwindow +AlwaysOnTop
Gui, Add, picture, x0 y0 w310 h104, %A_ScriptDir%\halfkeyboard_help.png
Gui, Show, w310 h104 NA, HalfKeyboard - permanent keyboard layout
Menu, Tray, Check, &Show Keyboard layout
}
Else
{
Gosub, GuiClose
}
Return

GuiClose:
Menu, Tray, UnCheck, &Show Keyboard layout
Gui, Destroy
Return

MenuExit:
ExitApp
Return

KeyDown:
Key:=A_ThisHotkey
If (KeyIsDown < 1 or Key <> LastKey)
{
KeyIsDown := True
LastKey := Key
Send %Key%
SetKeyDelay, 65535
SetTimer, ReplaceWithUpper, %UpperDelay%
}
Return

KeyUp:
Key:=A_ThisHotkey
SetTimer, ReplaceWithUpper, Off
SetTimer, ReplaceWithUpperMirror, Off
KeyIsDown := False
Return

ReplaceWithUpper:
SetKeyDelay, -1
Send {Backspace}+%LastKey%
Return

ReplaceWithUpperMirror:
SetKeyDelay, -1
Send {Backspace}+%MirrorKey%
Return

C# 6 Summary

C# No Comments

Short and incomplete notes on Rob Conery Pluralsight course “Exploring C# 6 with Jon Skeet”

  • Auto-properties
    Immutability
    Old way (still can set anywhere within the class)

    public string Name {get; private set;}

    New way (can be set only in a constructor or initializer)

    public string Name{get;}

     
    Initializers

    public string Name{get;} = "J";

    •  

  • Expression-bodied members
    For Properties
    Old way

    public Timespan Age{ get {return DateTime.UtcNow - DateOfBirth;}

    New way

    public Timespan Age => return DateTime.UtcNow - DateOfBirth;

     
    For Methods
    Old way

    public int GetName() {return "Joe";}

    New way

    public int GetName() => "Joe";

    •  

  • nameof
    Old way
    Use string literal; expression tree, or [CallerMemberName] attribute
    New way
    nameof(propertyName)

    •  

  • Using Static
    Old way

    Math.Sin(x)
SomeEnum.EnumName

    New way

    using static System.Math;
using static SomeEnum
...
Sin(x)
EnumName

    •  

  • String Interpolation
    $”{SomePropertyOrExpression} …”

    •  

  • Nullability
    Null Conditional Operator
    Old way

    return a!=null && a.b!=null && a.b.c=="abc";

    New way

    return a!.b!.c=="abc";

     
    Event Handlers
    Old way

    var handler = eventHandler;
if (handler !=null) {handler...}

    New way

    eventHandler?.Invoke...

    •  

  • Exception Filters 
    catch(WebException e) when(e.Status == ...)

Custom MVC Model Binder

C# MVC Web No Comments

When you expect data in non-standard way and you want it to magically bind to your model, custom model binders could be a way to go.

Let’s say we want to post xml data to our controller method and we have a model for it.

public class XmlModel
        {
            public int Number { get; set; }
        }

Which we want to accept in our controller method:

public ActionResult Xml(XmlModel xmlModel)
        {
            return Content(xmlModel.Number.ToString());
        }

Now, let’s add our xml binder:

public class XmlModelBinder : IModelBinder
    {
        public object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)
        {
            var modelType = bindingContext.ModelType;
            return new XmlSerializer(modelType).Deserialize(controllerContext.HttpContext.Request.InputStream);
        }
    }

And XMLModelBinderProvider:

public class XMLModelBinderProvider : IModelBinderProvider
    {      
        public IModelBinder GetBinder(Type modelType)
        {
            var contentType = HttpContext.Current.Request.ContentType;
            if (string.Compare(contentType, @"text/xml", StringComparison.OrdinalIgnoreCase) != 0)
            {
                return null;
            }

            return new XmlModelBinder();
        }
    }

Add the provider to our Application_Start method in the Global.asax:

ModelBinderProviders.BinderProviders.Insert(0, new XMLModelBinderProvider());

To test this we can use Composer from Fiddler:
http://localhost/home/xml
User-Agent: Fiddler
Content-Type: text/xml

Request Body:

<XmlModel>
<Number>42</Number>
</XmlModel>

If we add breakpoint in our controller, we should see 42 coming through in our model.