How to handle events of Buttons created at run time

How to handle events of Buttons created at run time

• Ronen Y

  using System;
  using System.Collections.Generic;
  using System.ComponentModel;
  using System.Data;
  using System.Drawing;
  using System.Text;
  using System.Windows.Forms;

  namespace WindowsApplication1
  {
      public partial class Form1 : Form
      {
          public Form1()
          {
              InitializeComponent();
          }

          private void Form1_Load(object sender, EventArgs e)
          {
              Button btn = new Button();
              btn.Text = "Click me";
              btn.Click += new EventHandler(btn_Click);
              this.Controls.Add(btn);
          }

          void btn_Click(object sender, EventArgs e)
          {
              MessageBox.Show("Clicked");
          }
      }
  }

  
  

• bryanandrews

  When creating the buttons, store some form of ID in the buttons' Tag property. Set the Click event of each to the same method, which would look like this:

  void btn_Click(object sender, EventArgs e)
  {
  Button btn = sender as Button;
  MyObj obj = LookupInDatabase(btn.Tag);
  this.Textbox1.Text = obj.Caption;
  }

  
  
  

• smaillet

  LucVK's answer is correct for WinForms, but if you are working with a WebForm, that step must be done in the CreateChildControls() virtual function.

  (As a side note, I'd always a good idea to mention if you are using a WinForm or a WebForm)

  
  

  
  
  

• groot

  H Ali Raza Shaikhi,

  Thanks for the reply, acctually my concern is, how to handle different click events for different buttons which comes from the database, take an example:-

  Suppose I have 10 names in the database, for these names 10 buttons are created at run time, now I want to display the caption of each button in a text box or label cotrol in the click event of each button.

  
  

• Binoy R B

  James Curran wrote:

  When creating the buttons, store some form of ID in the buttons' Tag property. Set the Click event of each to the same method, which would look like this: void btn_Click(object sender, EventArgs e) { Button btn = sender as Button; MyObj obj = LookupInDatabase(btn.Tag); this.Textbox1.Text = obj.Caption; }

  In case he just wants the caption of the button he could as well use this :

  void btn_Click(object sender, EventArgs e)
  {
  this.Textbox1.Text = ((Button)sender).Text;
  }

  Or in case the textbox differs depending on the button that was clicked :

  ((TextBox)this.Controls.Find(s, true)[0]).Text = "";

  With s being the string containing the name of the textbox - e.g. string.Concat("tb", ((Button)sender).Name)

  
  
  

• David Wilson

  Check out this MSDN Link, hope so this might help you
  
  http://msdn.microsoft.com/library/default.asp url=/library/en-us/vbcon/html/vbtskCreatingEventHandlersAtRuntime.asp
  
  
• How to handle events of Buttons created at run time