Open Windows Form based on CheckBox Checked (Selected) using C# and VB.Net

Hi supriyan,

Check this example. Now please take its reference and correct your code.

Form Design

In the main Form i have added 4 CheckBoxes and a Button.

I have added 4 Form to open on Button Click based on the checked CheckBoxes.

Code

Form1

C#

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
        this.CenterToScreen();
    }

    private void btnOpen_Click(object sender, EventArgs e)
    {
        if (chkForm2.Checked)
        {
            Form2 frm = new Form2();
            frm.Show();
        }

        if (chkForm3.Checked)
        {
            Form3 frm = new Form3();
            frm.Show();
        }

        if (chkForm4.Checked)
        {
            Form4 frm = new Form4();
            frm.Show();
        }

        if (chkForm5.Checked)
        {
            Form5 frm = new Form5();
            frm.Show();
        }
        this.Hide();
    }
}

VB.Net

Public Partial Class Form1
    Inherits Form

    Public Sub New()
        InitializeComponent()
        Me.CenterToScreen()
    End Sub

    Private Sub btnOpen_Click(ByVal sender As Object, ByVal e As EventArgs)
        If chkForm2.Checked Then
            Dim frm As Form2 = New Form2()
            frm.Show()
        End If

        If chkForm3.Checked Then
            Dim frm As Form3 = New Form3()
            frm.Show()
        End If

        If chkForm4.Checked Then
            Dim frm As Form4 = New Form4()
            frm.Show()
        End If

        If chkForm5.Checked Then
            Dim frm As Form5 = New Form5()
            frm.Show()
        End If

        Me.Hide()
    End Sub
End Class

Form2

C#

public partial class Form2 : Form
{
    public Form2()
    {
        InitializeComponent();
        this.Size = new Size(280, 250);
        this.CenterToScreen();
    }

    private void Form2_FormClosed(object sender, FormClosedEventArgs e)
    {
        if (Application.OpenForms.Count == 1)
        {
            Form1 frm = new Form1();
            frm.Show();
        }
    }
}

VB.Net

Public Partial Class Form2
    Inherits Form

    Public Sub New()
        InitializeComponent()
        Me.Size = New Size(280, 250)
        Me.CenterToScreen()
    End Sub

    Private Sub Form2_FormClosed(ByVal sender As Object, ByVal e As FormClosedEventArgs)
        If Application.OpenForms.Count = 1 Then
            Dim frm As Form1 = New Form1()
            frm.Show()
        End If
    End Sub
End Class

Form3

C#

public partial class Form3 : Form
{
    public Form3()
    {
        InitializeComponent();
        this.Size = new Size(270, 240);
        this.CenterToScreen();
    }

    private void Form3_FormClosed(object sender, FormClosedEventArgs e)
    {
        if (Application.OpenForms.Count == 1)
        {
            Form1 frm = new Form1();
            frm.Show();
        }
    }
}

VB.Net

Public Partial Class Form3
    Inherits Form

    Public Sub New()
        InitializeComponent()
        Me.Size = New Size(270, 240)
        Me.CenterToScreen()
    End Sub

    Private Sub Form3_FormClosed(ByVal sender As Object, ByVal e As FormClosedEventArgs)
        If Application.OpenForms.Count = 1 Then
            Dim frm As Form1 = New Form1()
            frm.Show()
        End If
    End Sub
End Class

Form4

C#

public partial class Form4 : Form
{
    public Form4()
    {
        InitializeComponent();
        this.Size = new Size(260, 230);
        this.CenterToScreen();
    }

    private void Form4_FormClosed(object sender, FormClosedEventArgs e)
    {
        if (Application.OpenForms.Count == 1)
        {
            Form1 frm = new Form1();
            frm.Show();
        }
    }
}

VB.Net

Public Partial Class Form4
    Inherits Form

    Public Sub New()
        InitializeComponent()
        Me.Size = New Size(260, 230)
        Me.CenterToScreen()
    End Sub

    Private Sub Form4_FormClosed(ByVal sender As Object, ByVal e As FormClosedEventArgs)
        If Application.OpenForms.Count = 1 Then
            Dim frm As Form1 = New Form1()
            frm.Show()
        End If
    End Sub
End Class

Form5

C#

public partial class Form5 : Form
{
    public Form5()
    {
        InitializeComponent();
        this.Size = new Size(250, 220);
        this.CenterToScreen();
    }

    private void Form5_FormClosed(object sender, FormClosedEventArgs e)
    {
        if (Application.OpenForms.Count == 1)
        {
            Form1 frm = new Form1();
            frm.Show();
        }
    }
}

VB.Net

Public Partial Class Form5
    Inherits Form

    Public Sub New()
        InitializeComponent()
        Me.Size = New Size(250, 220)
        Me.CenterToScreen()
    End Sub

    Private Sub Form5_FormClosed(ByVal sender As Object, ByVal e As FormClosedEventArgs)
        If Application.OpenForms.Count = 1 Then
            Dim frm As Form1 = New Form1()
            frm.Show()
        End If
    End Sub
End Class

Screenshot