C application interface development foundation - form control (1) - form form

 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()