C# Windows Forms CheckBox Examples

Learn how to use CheckBoxes and handle various state events

This tutorial will help you learn the following concepts:

1. How to add numerous CheclBoxes in a Form programmatically.
2. How to autocheck or explicitly Check or Uncheck a CheckBox in C#.
3. How to Handle click event of the CheckBox:
4. How to handle the CheckedChanged event of a CheckBox in C#
5. How to manually Check or Uncheck a CheckBox
6. How to handle the CheckStateChanged event of a Button
7. How to set the CheckState value of a CheckBox
8. How to change the Appearance of a CheckBox in C#.

Example 1: Simple CheckBox Example

Learn CheckBox usage and how to handle Click and Checked events.

This example will comprise the following files:

• CheckBox.cs

Step 1: Create Project

1. The first step is to create a C# Project.
2. Go to FILE-->New-->Project to create a new project

Step 2: Write Code

Write Code as follows:

*(a). CheckBox.cs

Create a file named CheckBox.cs

Add the following imports

using System;
using System.Windows.Forms;

Create our namespace:

namespace Examples {

Extend the Form class:

  class Form1 : Form {

Create our Main() method

    public static void Main() {
      Application.EnableVisualStyles();
      Application.Run(new Form1());
    }

Define our constructor:

    public Form1() {

Set the text property of our Form and then add several checkbox controls onto it:

      Text = "CheckBox example";
      Controls.AddRange(new Control[] {checkBox1, checkBox2, checkBox3, checkBox4, checkBox5});

Set the checkBox's AutoCheck property to false:

      checkBox1.AutoCheck = false;

Handle click event of the CheckBox:

      checkBox1.Click += delegate {
        //checkBox1.Checked = !checkBox1.Checked;
        //checkBox1.Text = string.Format("{0}", checkBox1.CheckState);
      };

Here is how you handle the CheckedChanged event of CheckBox:

      checkBox2.CheckedChanged += delegate (object sender, EventArgs e) {
        checkBox2.Text = string.Format("{0}", checkBox2.CheckState);
      };

You can manually set Checked value as shown below:

      checkBox2.Checked = true;

You can also react to CheckStateChanged events as shown below:

      checkBox3.CheckStateChanged += delegate (object sender, EventArgs e) {
        checkBox3.Text = string.Format("{0}", checkBox3.CheckState);
      };

You can also set the CheckState property explicitly:

      checkBox3.CheckState = CheckState.Indeterminate;

If you want the CheckBox to allow 3 states rather than 2 then use the ThreeState property:

      checkBox3.ThreeState = true;

You can also change the appearance of a CheckBox using the Appearance property. You can assign it a Normal or a Button property:

      checkBox4.Appearance = Appearance.Button;

Here is how we instantiate our CheckBoxes:

    private CheckBox checkBox1 = new CheckBox();
    private CheckBox checkBox2 = new CheckBox();
    private CheckBox checkBox3 = new CheckBox();
    private CheckBox checkBox4 = new CheckBox();
    private CheckBox checkBox5 = new CheckBox();

Here is the full code

using System;
using System.Windows.Forms;
//end

namespace Examples {
    //end
  class Form1 : Form {
        //end
    public static void Main() {
      Application.EnableVisualStyles();
      Application.Run(new Form1());
    }
        //end

    public Form1() {
            //end
      Text = "CheckBox example";
      Controls.AddRange(new Control[] {checkBox1, checkBox2, checkBox3, checkBox4, checkBox5});
//end
      checkBox1.AutoCheck = false;
      //end
      checkBox1.Click += delegate {
        //checkBox1.Checked = !checkBox1.Checked;
        //checkBox1.Text = string.Format("{0}", checkBox1.CheckState);
      };
      //end
      checkBox1.Location = new System.Drawing.Point(30, 30);
      checkBox1.Text = string.Format("{0}", checkBox1.CheckState);

      checkBox2.CheckedChanged += delegate (object sender, EventArgs e) {
        checkBox2.Text = string.Format("{0}", checkBox2.CheckState);
      };
      //end
      checkBox2.Checked = true;
      //end
      checkBox2.Location = new System.Drawing.Point(30, 60);
      checkBox2.Checked = true;

      checkBox3.CheckStateChanged += delegate (object sender, EventArgs e) {
        checkBox3.Text = string.Format("{0}", checkBox3.CheckState);
      };
      //end
      checkBox3.CheckState = CheckState.Indeterminate;
      //end
      checkBox3.Location = new System.Drawing.Point(30, 90);
      checkBox3.Text = string.Format("{0}", checkBox3.CheckState);
      checkBox3.ThreeState = true;
      //end

      checkBox4.AutoCheck = false;
      checkBox4.Appearance = Appearance.Button;
      //end

      checkBox4.Click += delegate {
        //checkBox4.Checked = !checkBox4.Checked;
        //checkBox4.Text = string.Format("{0}", checkBox4.CheckState);
      };
      checkBox4.Location = new System.Drawing.Point(30, 120);
      checkBox4.Text = string.Format("{0}", checkBox4.CheckState);

      checkBox5.Appearance = Appearance.Button;
      checkBox5.CheckStateChanged += delegate (object sender, EventArgs e) {
        checkBox5.Text = string.Format("{0}", checkBox5.CheckState);
      };
      checkBox5.Checked = true;
      checkBox5.Location = new System.Drawing.Point(30, 150);
    }
    private CheckBox checkBox1 = new CheckBox();
    private CheckBox checkBox2 = new CheckBox();
    private CheckBox checkBox3 = new CheckBox();
    private CheckBox checkBox4 = new CheckBox();
    private CheckBox checkBox5 = new CheckBox();
    //end
  };
}

Run

Simply copy the source code into your C# Project,Build and Run. Alternatively download the code using the links provided below, then open the .csproj project, build and run.

Reference

Download the code using the below links:

Number	Link
1.	Download Example
2.	Follow code author

Example 2: GroupBox And CheckBox

This example will comprise the following files:

• GroupBoxAndCheckBox.cs

Step 1: Create Project

1. The first step is to create a C# Project.
2. Go to FILE-->New-->Project to create a new project.

Step 2: Write Code

Write Code as follows:

*(a). GroupBoxAndCheckBox.cs

Create a file named GroupBoxAndCheckBox.cs

Here is the full code

using System;
using System.Windows.Forms;

namespace Examples {
  class Form1 : Form {
    // The main entry point for the application.
    public static void Main() {
      Application.EnableVisualStyles();
      Application.Run(new Form1());
    }

    Form1() {
      this.StartPosition = FormStartPosition.Manual;
      this.Location = new System.Drawing.Point(400, 200);
      this.ClientSize = new System.Drawing.Size(300, 160);
      this.Text = "GroupBox and CheckBox example";

      this.group1.Parent = this;
      this.group1.Text = "Group 1";
      this.group1.Bounds = new System.Drawing.Rectangle(10, 10, 135, 140);

      this.check1.Parent = this.group1;
      this.check1.Location = new System.Drawing.Point(20, 20);
      this.check1.Text = "check 1";

      this.check2.Parent = this.group1;
      this.check2.Location = new System.Drawing.Point(20, 50);
      this.check2.Text = "check 2";
      this.check2.Checked = true;

      this.check3.Parent = this.group1;
      this.check3.Location = new System.Drawing.Point(20, 80);
      this.check3.Text = "check 3";

      this.group2.Parent = this;
      this.group2.Text = "Group 2";
      this.group2.Bounds = new System.Drawing.Rectangle(155, 10, 135, 140);

      this.check4.Parent = this.group2;
      this.check4.Location = new System.Drawing.Point(20, 20);
      this.check4.Text = "check 4";

      this.check5.Parent = this.group2;
      this.check5.Location = new System.Drawing.Point(20, 50);
      this.check5.Text = "check 5";

      this.check6.Parent = this.group2;
      this.check6.Location = new System.Drawing.Point(20, 80);
      this.check6.Text = "check 6";
      this.check6.Checked = true;
    }

    private GroupBox group1 = new GroupBox();
    private GroupBox group2 = new GroupBox();
    private CheckBox check1 = new CheckBox();
    private CheckBox check2 = new CheckBox();
    private CheckBox check3 = new CheckBox();
    private CheckBox check4 = new CheckBox();
    private CheckBox check5 = new CheckBox();
    private CheckBox check6 = new CheckBox();
  }
}

Run

Simply copy the source code into your C# Project,Build and Run. Alternatively download the code using the links provided below, then open the .csproj project, build and run.

Reference

Download the code using the below links:

Number	Link
1.	Download Example
2.	Follow code author