WINDOWS

PROGRAMMING
WINDOWS FORMS & GDI+
WINDOWS FORMS
INTRODUCTION
WINDOWS FORMS (WINFORMS)
Part of .NET Framework for creating desktop applications:
System.Windows.Forms namespace
effectively a wrapper over part of Windows API

Categories of classes:
core infrastructure (e.g. Application, Form)
controls derived from the Control class (e.g. Button, TextBox)
components not derived from the Control class (e.g. Timer,
ToolTip)
common dialog boxes (e.g. OpenFileDialog, PrintDialog)

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EVENT-HANDLING
Event-driven graphical user interface
Event handlers - methods that process events and perform tasks
Each control generating an event has an associated delegate that
defines the signature for event handlers
event delegates are multicast (they contain lists of method references)
once an event is raised, every method that the delegate references is called

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EVENT-HANDLING EXAMPLE
public class MyForm : Form
{
public MyForm()
{
FormClosing += new FormClosingEventHandler(OnClosing);
}

private void OnClosing(Object sender,

FormClosingEventArgs e)
{
if (MessageBox.Show("Sure to close?", "Question",
MessageBoxButtons.YesNo) == DialogResult.No)
{
e.Cancel = true;
}
}
}

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APPLICATION & FORM
APPLICATION
Class representing the entire Windows Forms application
Methods to
start and stop the application
i.e. start and stop the message loop
start and stop threads
process Windows messages
etc.

Properties with info about:

path to the executable file
path to application data directories
current culture
etc.

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FORM
Class representing a main window, dialog box, or MDI child window
Inheritance hierarchy:
Object
MarshalByRefObject
Component
Control
ScrollableControl
ContainerControl
Form
Most members inherited from parent classes
(most notably Control class)

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FORMS LIFETIME
1. Constructor
InitializeComponent()is called to create and initialize all child
controls added using the Form Designer (in Visual Studio)
2. Load
3. Activated
4. //...
5. FormClosing
6. FormClosed
7. [ Deactivate ]
8. Dispose (a part of the IDisposable interface)
use it for disposing any resources used by the form
9. Destructor (called by the Garbage Collector)

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FORMS SIZE AND POSITION
Visibility
Show(), Visible
Shown, VisibleChanged

Properties:
Region, Bounds, DesktopBounds, ClientRectangle
Left, Top, Width, Height
Right = Left + Width
Bottom = Top + Height
StartPosition
Location, DesktopLocation
Size, ClientSize
MinimumSize, MaximumSize
AutoSize, AutoSizeMode
WindowState, TopMost

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FORMS SIZE AND POSITION CONTD
Methods:
SetBounds(), SetDesktopBounds(),
SetDesktopLocation()
BringToFront(), SendToBack()
SizeFromClientSize()

Events:
ClientSizeChanged, SizeChanged
LocationChanged
MaximumSizeChanged, MinimumSizeChanged
Resize, ResizeBegin, ResizeEnd

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FORMS APPEARANCE
Properties and methods for manipulating:
colors of different elements of the form
background images
fonts
icon, cursor icon
system buttons (minimize box, maximize box, help)
whether or not the form is visible
on the taskbar
opacity of the form
and more

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MODEL AND MODELESS FORMS
Modal Modeless

Has to be closed before using the Allows to shift focus between

rest of the application different forms in the application

ShowModal() Show()
ShowDialog()

AcceptButton, Close()
CancelButton, FormClosing, FormClosed
DialogResult

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CONTROLS:
BASE CLASSES
CONTROLS BASE CLASSES
Component - base class for all classes within the
System.Windows.Forms namespace
Control - message routing, keyboard and mouse, security, size
and position, HWND
Controls property - collection of child controls
ScrollableControl - auto-scrolling
ContainerControl - hosting other controls, focus, tab order
UserControl - composite control consisting of one or more
controls

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CONTROL CLASSES HIERARCHY
Object
MarshalByRefObject
Component
ErrorProvider, ImageList, NotifyIcon, Timer, ToolTip, ...
Control

System.Windows.Forms
ButtonBase, Label, ListView, PictureBox, ProgressBar, ScrollBar,
TreeView, ...
ScrollableControl
Panel, ToolStrip
ContainerControl
PropertyGrid, SplitContainer, ToolStripContainer, ToolStripPanel, ...
UserControl
Form

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CONTROL CLASS
Size and location
mostly the same as in Form
or, actually, the other way round

Auto-placement and auto-resize

Anchor position relative to the edge of its container
Dock

Z-order
BringToFront(),
SendToBack()

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CONTROL CLASS CONTD
Styles:
SetStyle(), GetStyle(), UpdateStyles()
Tag allows associating custom data (of any type) with the control
Tabbing
TabStop
TabIndex

Focus
ControlStyles.Selectable

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CONTROL CLASS CONTD
Parent-child relationships:
Controls collection of all child controls
HasChildren returns true if the control has child controls
Parent the control object that contains this control (may be null)
TopLevelControl - control at the very top of the controls hierarchy

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CONTROL CLASS CONTD
Ambient properties
using parents values if not set
e.g. BackColor

To apply operating system visual theme to control

Application.EnableVisualStyles()
Accessibility support
Aim: application available for users with disabilities
AccessibleXXX

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SCROLLABLECONTROL
Support for auto-scrolling behaviour
Enabling auto-scrolling:
1. AutoScroll = true
2. AutoScrollMinSize =

AutoScrollPosition
VScroll, HScroll visibility of scroll bars
Scroll event notification of scrolling

Usually not used directly:

use Panel instead

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CONTAINERCONTROL
A control that can function as a container for other controls
Focus management
Useful properties:
ActiveControl
ParentForm

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USERCONTROL
Composite controls
Reusable portions of the user interface
Similar to forms, but have no border, title bar and cannot be top-
level windows
Allow usage of standard controls with their functionality and
appearance

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COMMON CONTROLS
COMMON CONTROLS TOOLBOX

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LABELS
Label
read only text and/or image
usually description of a control or a form

LinkLabel
derived from Label
can display hyperlinks

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TEXT CONTROLS
Used for text input (surprise ;-))
Derived From TextBoxBase
Keyboard shortcuts can be used (e.g. Ctrl+C, Ctrl +V)
TextBox
MaskedTextBox
Allows to control input format
RichTextBox
Text input control with
advanced formatting options

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UPDOWNBASE (SPIN BOXES)
NumericUpDown
Value
Minimum, Maximum, Increment
DecimalPlaces, Hexadecimal, ThousandsSeparator
UpButton(), DownButton()

DomainUpDown
Sorted
Wrap
UpButton(), DownButton()

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BUTTONS
ButtonBase
base class for Button, CheckBox, RadioButton
Button
PerformClick()
DialogResult
Mnemonics, e.g. "&Cut && Paste

CheckBox
Can have 2 or 3 check states (ThreeState)

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LIST CONTROLS
Display lists of items in various graphical formats
Can be bound to a data source (more details later)
ListControl
base class for ListBox, CheckedListBox and ComboBox
Elements common to all list controls:
Items, Text, SelectedItem
Sorted
FindString(), FindStringExact()

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LIST CONTROLS CONTD
ListBox
Single or multiple selection
CheckedListBox
derived from ListBox
multiple items can be checked
cant be bound to a data source

ComboBox
single selection
possibility to enter a new value

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LISTVIEW
List of items (ListViewItem) + optionally
icons
check boxes
additional information

Several view modes

small icons
large icons
details

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TREEVIEW
Used for displaying hierarchical data
Nodes can be expanded/collapsed
Nodes collection
Contains only top-level nodes
Each node has a collection of child nodes

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DATE & TIME CONTROLS
DateTimePicker
customizable appearance
Format, CustomFormat
MinDate, MaxDate
ShowCheckBox, ShowUpDown
Value, Text
MonthCalendar
customizable appearance
MinDate, MaxDate, TodayDate
BoldedDates, MonthlyBoldedDates, AnnuallyBoldedDates
ShowToday, ShowTodayCircle, ShowWeekNumbers
SelectionStart, SelectionEnd, SelectionRange

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OTHER USEFUL CONTROLS
PictureBox
including various resizing modes
ProgressBar
providing various display styles
WebBrowser
wrapper for the Internet Explorers ActiveX control
Url, Navigate()
GoBack(), GoForward(), GoHome(), GoSearch()
Navigating, Navigated, DocumentCompleted
C# - Javascript interoperation possible

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BASIC GRAPHICAL COMPONENTS
ToolTip
SetToolTip(Control, string), GetToolTip
One tooltip can be assigned to multiple controls

NotifyIcon
Icon
ContextMenu
Text for icons tooltip
Visible

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CONTAINERS
Panels
Panel
FlowLayoutPanel
dynamically lays out its content horizontally or vertically
TableLayoutPanel
lays out its contents in a grid

GroupBox
frame and caption around a group of controls
often used to group radio buttons

SplitContainer
two panels separated by a movable splitter

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TABCONTROL
TabPages collection of TabPage objects
SelectedIndex, SelectedTab
SelectTab(), DeselectTab()
Deselecting, Deselected, Selecting, Selected

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MENUS & TOOLBARS
MENUS & TOOLBARS TOOLBOX

ContextMenu

MainMenu

StatusBar

ToolBar

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TOOLSTRIP & STATUSSTRIP
ToolStrip - represents a toolbar
StatusStrip represents a status bar
Can host various controls, e.g. dropdown, button, progress bar etc.
or custom controls
Advanced layout capabilities, e.g. overflow, docking and rafting

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MENUSTRIP & CONTEXTMENUSTRIP
MenuStrip
derived from ToolStrip
hosts:
ToolStripMenuItem, ToolStripComboBox, ToolStripSeparator, ToolStripTextBox
Form.MainMenuStrip
ContextMenuStrip
derived from ToolStripDropDownMenu
Control.ContextMenuStrip

Mnemonics
Accelerators (independent of mnemonics):
ShortcutKeys, ShowShortcutKeys,
ShortcutKeyDisplayString
ToolStripManager, ToolStripRenderer

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OTHER CONTROLS & COMPONENTS
BASIC COMPONENTS
Background worker
simplifies executing operations on background threads
DirectoryEnty, DirectorySearcher
encapsulate ActiveDirectory interactions
EventLog
provides access to Windows Event Log
FileSystemWatcher
provides notification about changes in the file system
HelpProvider
provides help
ImageList
manages a collection of images

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BASIC COMPONENTS
PerformanceCounter
represents Windows performance counter
Process
allows process manipulation (e.g. starting and controlling external
applications)
SerialPort
represents serial port
ServiceController
allows Windows services manipulation
Timer
one of several timers available

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VALIDATION
Control
CausesValidation
Validating (allows canceling), Validated

ContainerControl
AutoValidate
Validate(), ValidateChildren()

ErrorProvider
SetIconAlignment, SetIconPadding
BlinkStyle, BlinkRate
ContainerControl
(when used with data-bound control)
SetError(control, message)

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DIALOGS TOOLBOX

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OTHER TOOLBOX GROUPS
Printing support Reporting support

Database support for ADO.NET WPF Interoperability

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DATA BINDING
DATA BINDING
Mechanism for connecting control properties with data
(one-way or two-way)
Simple binding: single values
Complex data binding: collections
Typical usage:
DataGridView and DataSet
DataSet
represents relational data (incl. tables and relations)
supports multiple data views
supports data changes tracking
DataGridView
designed for presentation and modification of tabular data
extensive support for binding - especially to DataSets and DataTables
DATA SOURCE
Simple binding
Control.DataBindings.Add
(propertyName, dataSource, dataMember)

Complex binding:
DataGridView
DataSource
DataMember
ListBox, ComboBox,
DataSource
DisplayMember, ValueMember, SelectedValue

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DATA BINDING COMPONENTS
BindingSource
component encapsulating data source to simplify binding
(both simple & complex)
currency management
change notifications

ContainerControl.BindingContext
manages collection of instances of BindingManagerBase:
PropertyManagers for simple binding
CurrencyManagers for complex
binding

this.BindingContext[DataItems].Position += 1;

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CUSTOM CONTROLS
CUSTOM CONTROLS
Composite control (user control)
composition of Windows Forms controls in a common container
(UserControl)
the only choice with design-time support

Extended control (derived control)

inherited from an existing Windows Forms control
functionality extended
OnPaint() method overriden to create a custom appearance

Custom control
inherited from one of the base control classes
Component, Control, ScrollableControl, ContainerControl
the most flexible (and the most time-consuming) way to create controls

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VISUAL STUDIO SUPPORT
Every time a class library is compiled, Visual Studio scans through
the classes it contains, and adds each component or control to a
special temporary tab at the top of the Toolbox
The first time a control is added to a project (e.g. by dragging from
the Toolbox), Visual Studio:
adds a reference to the assembly where the control is defined
copies this assembly to the project directory

Toolbox can be customized

toolbox is a user-specific Visual Studio setting, not a project-specific setting

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DESIGN TIME ISSUES
Easily add and configure the control at design time
Serializing control configuration steps into the form code (for
correct initialization at runtime)
Ensuring the control behaves properly at runtime (e.g. more or less
the same appearance as at design time)
Design-time shortcuts for complex configuration tasks
Using licensing to differentiate between development and runtime
use of a control, restricting use according to a custom license policy

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DESIGN TIME SUPPORT
Control.DesignTime
Attributes:
supply information that will be used in the Properties window
attach other design-time components to the control and configure how
properties are serialized
Type converters
allow complex or unusual data types to be converted to and from
representations in more common data types
generate the initialization code required to instantiate a complex type

Type editors
provide graphical interfaces for setting complex type values

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DESIGN TIME ATTRIBUTES
For classes:
DefaultPropertyAttribute
DefaultEventAttribute

For properties:
DefaultValueAttribute
EditorAttribute
LocalizableAttribute
TypeConverterAttribute

For properties and events:

BrowsableAttribute
CategoryAttribute
DescriptionAttribute

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TYPECONVERTERS & UITYPEEDITORS
Custom TypeConverter overrides:
CanConvertFrom(), CanConvertTo()
ConvertFrom(), ConvertTo()
IsValid()

Custom UITypeEditor overrides:

EditValue(), GetEditStyle()
optionally: GetPaintValueSupported(), PaintValue()

Several dozen prebuilt implementations of both classes available

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EDITING CUSTOM TYPES
Alternatives:
edit as a string - requires a TypeConverter
edit with a drop-down UI - requires a UITypeEditor
edit with a modal dialog box - requires a UITypeEditor

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MOUSE & KEYBOARD
MOUSE
Mouse events
MouseMove, MouseDown, MouseUp, MouseClick, MouseDoubleClick
MouseEnter, MouseHover, MouseLeave, MouseWheel
Click, DoubleClick
MouseEventArgs:
{Button, Clicks, Delta, Location, X, Y}
Cursor class
can be loaded from a stream, file, program, or the systems resources
Form.Cursor
Cursors class standard cursors, e.g. Cursors.WaitCursor

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KEYBOARD
Events:
KeyDown
KeyEventArgs:
{KeyCode, KeyData, Modifiers, Alt, Control, Shift, Handled, SuppressKeyPress)
KeyPress
KeyPressEventArgs:
{KeyChar, Handled}
KeyUp
KeyEventArgs

Keys enum
e.g. Keys.Q, Keys.F5, Keys.LShiftKey

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FOCUS
Current focus:
CanFocus, Focused
ContainsFocus() (including children)
Focus()

Activating controls:
CanSelect
Select(), SelectNextControl()
Form.ActiveControl

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FOCUS EVENTS

KEYBOARD / SELECT() MOUSE / FOCUS()

Enter Enter
GotFocus GotFocus
Leave LostFocus
Validating Leave
Validated Validating
LostFocus Validated

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PREPROCESSING INPUT MESSAGES
PreProcessMessage
virtual method on Control class
messages pre-processed: WM_KEYDOWN, WM_SYSKEYDOWN, WM_CHAR,
WM_SYSCHAR
return:
true for processed messages
base.PreProcessMessage otherwise

More specialized methods:

IsInputChar(), IsInputKey()
ProcessCmdKey()
ProcessDialogChar(), ProcessDialogKey()

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RESOURCES
RESOURCES
An assembly is a collection of types and optional resources
the binary data, text files, audio files, video files, string tables, icons,
images, XML files
Localized applications
a problem with multilingual user interface
for each resource added to an assembly, it is possible to specify the culture
information (a language and country, e.g. "pl-PL", "en-US", "de-De", "de-
AT")
satellite assemblies

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TYPED RESOURCE FILES
Language=Polish
.txt Next=Nastpna strona
Prev=Poprzednia strona
textual name/value format
an easy way to add string resources

.resx
the XML format
support for both strings and other objects such as images

.resources
the binary format
a binary equivalent of the XML file
the only format that can be embedded in an assembly, the other formats
must be converted

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CREATING .RESX FILES
ResXResourceWriter w =
new ResXResourceWriter(@"C:\myRes.resx");

Image img = new Bitmap("pattern.bmp");

w.AddResource("background", img);

w.AddResource("Next", "Nastpny");

w.Generate();
w.Close();

<?xml version="1.0" encoding="utf-8"?>

<root>
(...)
<data name="background"
type="System.Drawing.Bitmap, System.Drawing"
mimetype="application/x-microsoft.net.object.bytearray.base64">
<value>
Qk32BAAAAAAAAHYAAAAoAAAAMAAAADAAAAABAAQ
AAAAAAAAAAADDDgAAww4AABAAAAAQAAAAAAAA/w
...
</value>
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CREATING .RESOURCES FILES
From .resx or .txt file
resgen myRes.resx myRes.resources
resgen polish.txt polish.resources

Using C#
ResourceWriter rw =
new ResourceWriter(@"C:\myRes.resources");

Image img = new Bitmap("pattern.bmp");

w.AddResource("background", img);

w.AddResource("HelloWorld", "Witaj wiecie");

w.Generate();
w.Close();

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RETRIEVING RESOURCES

ResourceManager rm =
new ResourceManager("myApp.myRes",
Assembly.GetExecutingAssembly());

MessageBox.Show(rm.GetString("HelloWorld"));

pictureBox.Image =
(Bitmap)rm.GetObject("background");

rm.ReleaseAllResources();

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RESOURCES WITH VISUAL STUDIO
Adding resources
in resx files:
Project > Add New Item > Resources File
or: Project > Properties > Resources
a property in a special class is generated for easier access to resource

Editing resources
Visual Studio built-in editors
the binary editor, image editor
external editors (e.g. the Paint for image files)
other applications can be associated with types of resources

Compiling resources into assemblies

resgen.exe tool is called automatically

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USING THE SOURCE CODE GENERATED BY VS
public class Resource1
{
public static string String1
{
get { return ResourceManager.GetString(
"String1", resourceCulture); }
}
public static System.Drawing.Bitmap FeatherTexture
{
get
{
object obj = ResourceManager.GetObject(
"FeatherTexture", resourceCulture);
return ((System.Drawing.Bitmap)(obj));
}
}
} pictureBox1.Image = Resource1.FeatherTexture;
label1.Text = Resource1.String1;
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LOCALIZING APPLICATIONS
Retrieved resources language:
ResourcesManager.Get...(name, culture)
Thread.CurrentUICulture
VS-generated helper class:
Resources.Culture

Default data formatting language:

Thread.CurrentCulture
Keyboard input language:
InputLanguage.InstalledInputLanguages, InputLanguage.DefaultInputLanguage,
InputLanguage.CurrentInputLanguage
Application.CurrentInputLanguage

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MANIFEST RESOURCES
Another method for embedding resources in assembly
without use of .resource files
all resources stored as untyped binary data

Adding resource:
add file to the project
in its Properties, set Build Action: Embedded Resource

Retrieving resource:
Assembly.GetManifestResourceStream
type-specific methods
e.g. one of Bitmap class constructors
APPLICATION SETTINGS
APPLICATION SETTINGS
THE OLD WAY
.config files (XML)
special naming convention [executableFileName].config
can be read and modified by applications

<configuration>
<appSettings>
<add key="welcome" value="Hello, user!"/>
<add key=bye" value=Farewell!"/>
</appSettings>
</configuration>

AppSettingsReader reader = new AppSettingsReader();

string s = (string)reader.GetValue("welcome,
typeof(string));

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APPLICATION SETTINGS THE NEW (STRONGLY TYPED) WAY
<configuration>
<configSections>
<sectionGroup name="userSettings
type="System.Configuration.UserSettingsGroup, System,
Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" >
<section name="Tests.Settings1
type="System.Configuration.ClientSettingsSection, System,
Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089
allowExeDefinition="MachineToLocalUser"
requirePermission="false" />
</sectionGroup>
<sectionGroup name="applicationSettings
type="System.Configuration.ApplicationSettingsGroup, System,
Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" >
<section name="Tests.Settings1
type="System.Configuration.ClientSettingsSection, System,
Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089
requirePermission="false" />
</sectionGroup>
</configSections>
...
</configuration>

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APPLICATION SETTINGS THE NEW (STRONGLY TYPED) WAY

<configuration>
...
<userSettings>
<Tests.Settings1>
<setting name="Setting1" serializeAs="String">
<value>test</value>
</setting>
</Tests.Settings1>
</userSettings>
<applicationSettings>
<Tests.Settings1>
<setting name="Setting2" serializeAs="String">
<value>test2</value>
</setting>
</Tests.Settings1>
</applicationSettings>
</configuration>

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 APPLICATION SETTINGS THE NEW WAY VS SUPPORT

Defined in separate .settings files

var setting2Value = Settings1.Default.Setting2;

Settings1.Default.Setting1 = "Test";
DateTime time = Settings1.Default.Setting3;
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MESSAGE HANDLING HOOKS
APPLICATION.ADDMESSAGEFILTER()

public class TestMessageFilter : IMessageFilter

{
public bool PreFilterMessage(ref Message m)
{
//Blocks all the messages relating
//to the left mouse button.
if (m.Msg >= 513 && m.Msg <= 515)
{
Console.WriteLine("Processing the messages :
+ m.Msg);
return true;
}
return false;
}
}
Application.AddMessageFilter(new TestMessageFilter());

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OVERRIDING WINDOW PROCEDURE
Message: {HWnd, LParam, Msg, Result, WParam}
Form.Handle HWND

private const int HTCAPTION = 0x0002;

private const int WM_NCHITTEST = 0x0084;

protected override void WndProc(ref Message m)

{
switch (m.Msg)
{
case WM_NCHITTEST:
m.Result = (IntPtr)HTCAPTION;
break;
default:
base.WndProc (ref m);
break;
}
}

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GDI+
GDI+
Successor to Windows Graphics Device Interface (GDI)
supports GDI for compatibility with existing applications
optimizes many of the capabilities of GDI
provides additional features

Class-based application programming interface (API)

two independent implementations: .NET (managed code) and unmanaged
code
Availability:
included in Windows XP+ and Windows Server 2003+
redistributable for NT 4.0 SP6, 2000, 98, Me
Gdiplus.dll

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NEW FEATURES
Gradient brushes (linear and path)
for filling shapes, paths and regions
Cardinal splines
Independent path objects (GraphicsPath objects)
Transformations, Matrix object
Transformations of regions
Alpha blending
Image formats:
BMP, GIF, JPEG, Exif, PNG, TIFF, ICON, WMF, EMF

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GRAPHICS CLASS
Graphics class:
core of GDI+
Device Context equivalent
associated with a particular window on the screen
contains attributes that specify how items are to be drawn
improvements (compared to DC):
less state:
pens, brushes, paths, images, and fonts as method parameters
no current position for drawing lines
separate methods for draw and fill

GDI object equivalents:

represented as true objects
in .NET: implement IDisposable

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USING GRAPHICS
Obtaining Graphics object:
Paint event handler: PaintEventArgs.Graphics
Control.CreateGraphics()
Graphics: FromHdc(), FromHwnd(), FromImage()

Triggering the Paint Event:

Control.Invalidate()
Control.Update(), Control.Refresh()

Flicker-free drawing: this.DoubleBuffered = true

private void AboutForm_Paint(object sender, PaintEventArgs e)

{
e.Graphics.FillRectangle(Brushes.White, 0, 0, 200, 100);
using (Pen mP = new Pen(Color.Red, 3)) {
e.Graphics.DrawLine(mP, 20, 10, 90, 90);
}
}
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SIMPLE SHAPES
Simple figures:
DrawLine(), DrawRectangle(), DrawEllipse(), DrawArc(), DrawPolygon()
FillEllipse(), FillPie(), FillPolygon(), FillRectangle()

Cardinal splines:
DrawCurve(), DrawClosedCurve()
FillClosedCurve()

Bezier splines:
DrawBezier(), DrawBeziers()

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PATHS
Formed by combining lines, rectangles, and simple curves
GraphicsPath class:
adding simple figures:
AddLine(), AddRectangle(), AddEllipse(), AddArc(), AddPie(), AddBezier(),
AddCurve(), AddClosedCurve(), AddPolygon(), AddString()
joining two paths: AddPath()

Graphics.DrawPath()
Graphics.FillPath()

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REGIONS
Describe interiors of graphics shapes composed of rectangles and
paths
Region class
Hit testing
Region.IsVisible(point, graphics)
Clipping
Graphics.SetClip(region)

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BRUSHES
Brush abstract base class for all brushes:
SolidBrush, HatchBrush, TextureBrush, LinearGradientBrush,
PathGradientBrush

using (SolidBrush solidBrush =

new SolidBrush(Color.FromArgb(255, 255, 0, 0))) {
e.Graphics.FillEllipse(solidBrush,0,0,100,60);
}

using (HatchBrush hBrush =

new HatchBrush(HatchStyle.Horizontal,
Color.Green, Color.Blue) {
e.Graphics.FillEllipse(hBrush,100,0,100,60);
}

Image image = new Bitmap("texture.jpg");

TextureBrush tBrush = new TextureBrush(image);
e.Graphics.FillEllipse(tBrush,200,0,100,60);

Karol Waldzik - Windows Programming 96

PENS
Attributes
Width
Alignment (PenAlignment enumeration)
Line caps:
StartCap, EndCap (LineCap enumeration)
CustomStartCap, CustomEndCap (CustomLineCap class)
LineJoin (LineJoin enumeration)
DashStyle, DashPattern, DashCap
Brush

var image = Image.FromFile("texture.jpg");

var Brush = new TextureBrush(image);
var texturedPen = new Pen(tBrush, 30);
e.Graphics.DrawLine(texturedPen, 0, 0, 50, 50);

Karol Waldzik - Windows Programming 97

IMAGES
Image abstract base class
Bitmap derived from Image
contains specialized methods for loading, displaying, and manipulating
raster images
Graphics.DrawImage()
many overrides available
flexible resizing/cropping possibilites
influenced by Graphics.InterpolationMode
influenced by Graphics.Transform

Karol Waldzik - Windows Programming 98

IMAGE ENCODERS/DECODERS
Listing installed encoders and decoders:
ImageCodecInfo.GetImageEncoders(),
ImageCodecInfo.GetImageDecoders()
return arrays of ImageCodecInfo

public void ConvertImage(string srcPath, string destPath,

ImageFormat destFormat)
{
Image image = new Bitmap(srcPath);
image.Save(destPath, destFormat);
}

try {
ConvertImage(bird.jpg, bird.png, ImageFormat.Png);
}
catch (Exception exc) { }
Karol Waldzik - Windows Programming 99
TEXT
Graphics.DrawString()
at specified location
in a rectangle
StringFormat argument:
Alignment, LineAlignment
SetTabStops()
FormatFlags
TextRenderingHint allows switching on antialiasing

Karol Waldzik - Windows Programming 100

FONTS
Font class
Metrics
Font.GetSize()
FontFamily.GetEmHeight()
FontFamily.GetCellAscent()
FontFamily.GetCellDescent()
FontFamily.GetLineSpacing()

Font font = new Font("Arial", 16,

FontStyle.Regular);

Karol Waldzik - Windows Programming 101

TRANSFORMATIONS
Matrix class
Graphics.Transform
helper methods:
ScaleTransform()
RotateTransform()
TranslateTransform()

Transformation order is significant

Karol Waldzik - Windows Programming 102

GRAPHICS CONTAINERS
GraphicsContainer class
Stores state of Graphics:
link to device context
quality settings
transformations
clipping region
Pen pen = new Pen(Color.Red);
Alternative: gr.TranslateTransform(100.0f, 80.0f);
Graphics.Save()
GraphicsContainer
graphicsContainer = gr.BeginContainer();
gr.RotateTransform(30.0f);
gr.DrawRectangle(pen,-60,-30,120,60);
gr.EndContainer(graphicsContainer);

gr.DrawRectangle(pen,-60,-30,120,60);

Karol Waldzik - Windows Programming 103