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c#keydownshowdialogsubmit-buttonwindows-mobile-5.0

Submit FORM on ENTER key pressed


OS: Windows Mobile 5 / Compact .NET Framework (Form.AcceptButton() NOT available)
I am showing a modal form with ShowDialog(). I want to be able to submit the modal form on hitting the ENTER key. I am able to grab the KEYDOWN EVENT when ENTER key is pressed.
Any other solution will be appreciated too.

public class Prompt
        {
            public static string AcceptTagPrice()
            {
                Form prompt = new Form();
                prompt.WindowState = System.Windows.Forms.FormWindowState.Maximized;
                prompt.TopMost = true;
                prompt.BackColor = System.Drawing.Color.White;
                prompt.KeyPreview = true;
                prompt.MaximizeBox = true;
                Label textLabel = new Label() { Text = "Enter Price", Left = 20, Top = 50, Width = 200, TextAlign = ContentAlignment.TopCenter, ForeColor = System.Drawing.Color.Green, Font = new System.Drawing.Font("Tahoma", 11F, System.Drawing.FontStyle.Bold) };
                TextBox textBox = new TextBox() { Left = 20, Top = 100, Size = new System.Drawing.Size(202, 31), BackColor = System.Drawing.Color.LightGray }; ;
                Button confirmation = new Button() { Text = "Submit", Left = 30, Top = 140, Size = new System.Drawing.Size(121, 33), BackColor = System.Drawing.Color.LightSkyBlue };
                confirmation.Click += (sender, e) => { bool k = IsValidPrice(textBox.Text); if (k) { prompt.Close(); } else { textBox.Focus(); } };
                prompt.KeyDown += new System.Windows.Forms.KeyEventHandler(Prompt.ModalForm_KeyDown);
                prompt.Controls.Add(confirmation);
                prompt.Controls.Add(textLabel);
                prompt.Controls.Add(textBox);
                textBox.Focus();
                prompt.Activate();
                prompt.ShowDialog();
                return textBox.Text.ToString().Trim();
            }

            public static bool IsValidPrice(string price)
            {
                if (!Regex.IsMatch(price, @"^[0-9]\d*(\.\d+)?$"))
                {
                    MessageBox.Show("Please enter a valid price", "Error", MessageBoxButtons.OK, MessageBoxIcon.Exclamation, MessageBoxDefaultButton.Button1);
                    return false;
                }
                else
                {
                    return true;
                }
            }

            private static void ModalForm_KeyDown(object sender, KeyEventArgs e)
            {
                if (e.KeyData == Keys.Enter)
                {
                      Messagebox.Show("Enter Key Pressed");
                    // BUT DUNNO HOW TO TRIGGER CONFIRMATION BUTTON CLICK EVENT 
                }
            }
        }

Solution

  • I would recommend instead separating the button click into a method which you can then call

    Edited to account for Compacted Framework.

    Add a name property to your textBox

    TextBox textBox = new TextBox() { Name = "the_textBox" ....
    

    change your confirmation.Click to this

    confirmation.Click += (sender, e) => { Confirmation_Click(prompt); };
    

    add this method

    private static void Confirmation_Click(Form prompt)
    {
        TextBox textBox = prompt.Controls.Find("the_textBox", false).FirstOrDefault() as TextBox;
        if(textBox == null)
            return; //uhm weird
    
        bool k = IsValidPrice(textBox.Text);
        if (k)
            prompt.Close();
        else 
            textBox.Focus();
    }
    

    Replace your KeyDown Method with this

    private static void ModalForm_KeyDown(object sender, KeyEventArgs e)
    {
        Form form = sender as Form;
        if(form == null)
            return; //uhm weird
    
        if (e.KeyData == Keys.Enter)
        {
            Confirmation_Click(form);
        }
    }