How to call the same form(WinForm) in the desktop application using c#

Question

already i'm opened winform from there i have add to new form to get a search window in the search window ,if the user input some number from 1 to 10 again after clicking ok button in the search window.it should navigate to the same window which is opened initially and the content in the window has to change now in the front-end.

but in my case it is opening new window form instead how to fix this below are my code snippets:

  private void button1_Click(object sender, EventArgs e)
        {
            //FrmAttemptInstruction frmAttemptInstruction = new FrmAttemptInstruction() ;
            //Close(frmAttemptInstruction);
            //textvalue = textBox1.Text;            
            //this.ShowDialog(new FrmAttemptInstruction());


            if (Application.OpenForms.OfType<FrmAttemptInstruction>().Any())
            {
                //Application.OpenForms.OfType<FrmAttemptInstruction>().First().Close();
                FrmAttemptInstruction frmAttemptInstructions = new FrmAttemptInstruction();
                frmAttemptInstructions.Hide(); 
            }

            FrmAttemptInstruction frmAttemptInstruction = new FrmAttemptInstruction();
            textvalue = textBox1.Text;
            frmAttemptInstruction.Show();

        }

        private void Close(FrmAttemptInstruction frmAttemptInstruction)
        {

                frmAttemptInstruction.Close();
        }
    }

     protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }
in the above method i got issue in dispose method

Answer 1

Hi @vasanth ,

Do you mean that if the user enters the same number, the app opens a window that was already open before, and if a new number is entered, a new window is created?

// FrmAttemptInstruction.cs
public partial class FrmAttemptInstruction : Form
{
    // Property to store the number associated with the instruction
    public int Number { get; set; }

    public FrmAttemptInstruction()
    {
        InitializeComponent();
    }
}

// MainForm.cs
public partial class MainForm : Form
{
    // List to store all FrmAttemptInstruction instances
    private List<FrmAttemptInstruction> attemptInstructions = new List<FrmAttemptInstruction>();

    public MainForm()
    {
        InitializeComponent();
    }

    private void button1_Click(object sender, EventArgs e)
    {
        int inputNumber;
        if (int.TryParse(textBox1.Text, out inputNumber))
        {
            // Check if an existing instruction matches the input number
            FrmAttemptInstruction existingInstruction = attemptInstructions.FirstOrDefault(inst => inst.Number == inputNumber);
            if (existingInstruction != null)
            {
                // If an instruction for the input number exists, show it and hide others
                foreach (var instruction in attemptInstructions)
                {
                    if (instruction != existingInstruction)
                        instruction.Hide();
                }
                existingInstruction.Show();
            }
            else
            {
                // If no instruction for the input number exists, create a new one and manage visibility
                FrmAttemptInstruction newInstruction = new FrmAttemptInstruction();
                newInstruction.Number = inputNumber;
                attemptInstructions.Add(newInstruction);
                newInstruction.Show();

                foreach (var instruction in attemptInstructions)
                {
                    if (instruction != newInstruction)
                        instruction.Hide();
                }
            }
        }
        else
        {
            MessageBox.Show("Please enter a valid number!");
        }
    }
}

Best Regards.

Jiachen Li

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