Get List of all Open Forms in Windows Application

In this blog we learn how to get the list of all open forms by windows form application.

Step 1. Create new windows form application.

Step 2. Add three win forms as Form1, Form2 and Form3 to application.

Step 3. Design Form3 as follows.

Step 4. Write following code for Form3.

using System;  
using System.Collections.Generic;  
using System.ComponentModel;  
using System.Data;  
using System.Drawing;  
using System.Linq;  
using System.Text;  
using System.Windows.Forms;  
using System.Data.SqlClient;  
namespace WindowsFormsApplication1  
{  
    public partial class Form3 : Form  
    {  
        public Form3()  
        {  
            InitializeComponent();  
        }  
  
        private void Form3_Load(object sender, EventArgs e)  
        {  
            label3.Text = Application.OpenForms.Count.ToString();  
            foreach (Form frm in Application.OpenForms)  
            {  
                label1.Text = frm.Name;  
            }  
        }  
  
        private void button1_Click(object sender, EventArgs e)  
        {  
            Form1 frm1 = new Form1();  
            frm1.Show();  
        }  
  
        private void button2_Click(object sender, EventArgs e)  
        {  
            Form2 frm2 = new Form2();  
            frm2.Show();  
        }  
  
        private void button3_Click(object sender, EventArgs e)  
        {  
            label3.Text = Application.OpenForms.Count.ToString();  
            label1.Text = "";  
            foreach (Form frm in Application.OpenForms)  
            {  
                label1.Text += frm.Name + "\n";  
            }  
        }  
    }  
}

Step 5. Set Form3 as start up form.

Step 6. Run application

After running application you will get above output. It show the count of open form as 1 and that one form is Form3.

Step 7. Open Form1 and Form2 by clicking on button Form1 and Form2.

Step 8. Then click on Get list button to get list of open form as follows