C ＃ application interface development foundation - form control

From forms

establish WinForm Program

establish WinForm Procedure steps

open Visual Studio, Click on “ Create a new project ”, Using shortcut keys Ctrl+Shift+N It can be opened quickly “ New projects ” Dialog box .

Select... From the pull down menu “C#”、“Windows”、“ desktop ” in , Select in the list box “Windows Form application （.NET Framework）”.

Click on “ next step ”.

  Click on “ establish ”. 

  In Solution Explorer , double-click Program.cs file , Will jump to Windows Console application interface , stay “ edit ” In the window is an automatically generated WinForm Program .

  The code is as follows ：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApp1
{
    internal static class Program
    {
        /// <summary>
        ///  The main entry point for the application .
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.Run(new Form1());
        }
    }
}

Click again “ start-up ” Key , A blank form will pop up .

  The essence of creating a form

The essence of a form is to use System.Windows.Forms.Form Class or a derived class of this class .

Right click “ forms ” after , choice “ Look at the code ” command , It will jump to Form1.cs file .

The code is as follows ： 

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
    }
}

Add and delete forms

Right-click the project name WindowsFormsApp1, Choose... From the shortcut menu that pops up “ add to ”-“Windows forms ” perhaps “ add to ”-“ New item ” command .

Last in “ Add a new item ” Select... From the Christmas box “ forms （Windows forms ）”.

  Delete form , Just in the solution manager , Select the name of the form to delete , Right click , Select from the pop-up shortcut menu “ Delete ” Command is enough .

 

Properties of the form

1、“ attribute ” panel

open “ attribute ” The panel has the following three methods ：

（1）

Right click command

（2）

“ View ” command

（3）

The lower right corner

2、C# WinForm Form basic properties

（1） Attribute values in window styles , Can be used to change the icon 、 Maximize window transparency .

Window style

Property value	explain
Icon	Change icon style （ Top left Icon ）
MaximizeBox:true;	Display the maximize button in the upper right corner
MinimizeBox:true;	Display the minimize button in the upper right corner
ShowInco:true;	Display the small icon in the upper left corner
ShowInTaskbar:ture;	The form is displayed in the taskbar
TopMost:ture;	The window is displayed at the top
Opacity:100%	Whole window transparency

（2） Attribute values in the layout , It can be used to change the size of the form and the display position of the form after starting the program .

Layout

Property value	explain
AutoScroll:true/false;	If the control exceeds the window, whether to automatically display the scroll bar
AutoSize:true/false;	Whether the scope of the window will exceed the size of the control
MaximumSize:0,0;	The maximum size a window can be dragged
MinimumSize:0,0;	The smallest size a window can drag
Size:300,300;	The default size when the window is opened
StartPosition:centerScreen;	The default desktop location when the window is opened , In the middle
WindowState:Maximized;	The default open window is maximized .

（3） Attribute value of appearance , It is mainly used to change the form color 、 Font, title, etc .

appearance

Property value	explain
Font: Song style ,9pt;	You can change the font size , The larger the font, the larger the control
Text;	Input text
TextAlign;	Text location
FormBorderStyle：FixedSingle;	The window cannot be dragged
FormBorderStyle:None;	Hide the border of the window
DropDownStyle：DropDownList;	Make the drop-down box unable to enter text

3、 Set form properties

The icon of the form is system Default icon .

Change icon , stay “ attribute ” The palette , choice Icon character

Color of the form And background , adopt BackgroundImage Property to set . choice “ attribute ” In the panel BackgroundImage attribute .

Common events for forms

The so-called event , It means what's going to happen , It can be simply understood as the user's operation , It is triggered by an object . All events of the form , Can be in “ attribute ” Panel to view .

1、 Add event

Add an event to the form , Just select the event to be added in the event panel ,Load Double click in the following space , The corresponding event will be generated automatically .

（1） When the form is loaded , A form loading event will be triggered Load.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            MessageBox.Show(" Form loading completed ");
        }
    }
}

（2） When you click the form , Trigger Click（ single click ） event .

Click double-click .

The code is as follows ：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            MessageBox.Show(" Form loading completed ");
        }

        private void Form1_Click(object sender, EventArgs e)
        {
            MessageBox.Show(" Click form ");
        }
    }
}

 （3） When you close the form , Trigger FormClosing（ close ） event

  The code is as follows ：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            MessageBox.Show(" Form loading completed ");
        }

        private void Form1_Click(object sender, EventArgs e)
        {
            MessageBox.Show(" Click form ");
        }

        private void Form1_FormClosing(object sender, FormClosingEventArgs e)
        {
            MessageBox.Show(" Are you sure you want to close the form ？");
        }
    }
}

2、 Delete event

Do not understand , Don't master .

Display and hide of forms

Form identifier .Show()

Form identifier .Hide()

MDI forms

Single document interface （SDI）

Multi document interface （MDI）

MDI The concept of form

MDI forms （Multiple-Document Interface, Multi document interface ） Used to display multiple documents at the same time .

Used in projects MDI On the window , Usually a MDI Window form as parent form , A parent form can contain multiple child forms in its workspace .

Set up MDI forms

1、MDI Container form

Set a form as a window form , There are two ways ：

1、 On the window “ attribute ” The palette , take IsMidContainer Property is set to True that will do .

False：

 

 True：

 

2、 On the window Load Add the following statement to the event

The code is as follows ：

using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            this.IsMdiContainer = true;
        }
    }
}

 

2、 Set up MDI Subform

MDI A subform is a normal form . You only need to convert the MdiParent Property to a MDI Parent form , It is the child form of the parent form , The syntax is as follows ：

Form instance name .MdiParent= Parent form object ;

   Set up MDI Containers ：

After modification ：

 

from Form5 In the attribute , adopt Name Property to change to “MainForm”

After modification ：

Text Property represents the form title , It is amended as follows “MDI forms ”

After modification ： 

 

  New subform （Form1.cs、Form2.cs、Form3.cs、Form4.cs）： 

Code content ：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace Form5
{
    public partial class MainForm : Form
    {
        public MainForm()
        {
            InitializeComponent();
        }

        private void MainForm_Load(object sender, EventArgs e)
        {
            Form1 form1 = new Form1();
            form1.Show();
            form1.MdiParent = this;
            Form2 form2 = new Form2();
            form2.Show();
            form2.MdiParent = this;
            Form3 form3 = new Form3();
            form3.Show();
            form3.MdiParent = this;
            Form4 form4 = new Form4();
            form4.Show();
            form4.MdiParent = this;
        }
    }
}

After completion ：

 

 

The operation results are as follows ：

array MDI forms

The syntax is as follows ：

public void LayoutMdi(MdiLayout value)

value yes MdiLayout One of the enumeration values of , Used to define MDI Layout of subform .

MdiLayout Enumeration members of

Members of the enumeration	explain
Cascade	Cascade arrangement MDI Subform
TileHorizontal	Tile horizontally MDI Subform
TileVertical	Tile vertically MDI Subform

Create a new one Windows Forms application , stay Name Property to name the form unique identifier MainForm, And in Text Properties of the , Name the title of the main form “MDI forms ”.

Select from the menu bar “ View ” command , Re selection “ hold-all ” command , The toolbox will pop up .

 

Select... In the toolbox MenuStrip Control , A row of menu bars will appear in the form , And then enter “ New form ”、“ Cascade arrangement ”、“ Tile horizontally ”、“ Tile vertically ”、“ close ”.

 

next , then IsMdiContainer Property is set to True.

Create a subform , And named it “ChildForm”, Next, you can double-click the menu item , Add events . 

The code is as follows ：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace Form5
{
    public partial class MainForm : Form
    {
        public MainForm()
        {
            InitializeComponent();
        }

        private void MainForm_Load(object sender, EventArgs e)
        {
            Form1 form1 = new Form1();
            form1.Show();
            form1.MdiParent = this;
            Form2 form2 = new Form2();
            form2.Show();
            form2.MdiParent = this;
            Form3 form3 = new Form3();
            form3.Show();
            form3.MdiParent = this;
            Form4 form4 = new Form4();
            form4.Show();
            form4.MdiParent = this;
        }

        private void  New form ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            ChildForm mychildForm=new ChildForm();
            mychildForm.Show();
            mychildForm.MdiParent = this;
        }

        private void  Cascade arrangement ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            LayoutMdi(MdiLayout.Cascade);
        }

        private void  Tile horizontally ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            LayoutMdi(MdiLayout.TileHorizontal);
        }

        private void  Tile vertically ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            LayoutMdi(MdiLayout.TileVertical);
        }

        private void  close ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            Close();
        }
    }
}

The operation results are as follows ：

Click new form ：

 

 

Cascade arrangement ：

 

Tile horizontally ：

 

Tile vertically ： 

 

 

File control

Select class control

Group class control

menu bar 、 Toolbar and status bar controls