Creating a simple ButtonDropdown Control

Download source code - 16.07 KB

Introduction

This post helps to create a ButtonDropDown in Windows Form (I was not able to find a control in Visual Studio for my requirement, so I made one and I’m not sure whether there is one already). For this, I’m using a combination of Button control and ContextMenuStrip control.

The arrow in the button is an image with middle-right aligned.

Initialize a ContextMenuStrip with the required MenuItems
Register the click events of ContextMenuStripMenuItems
Pop out the context menu on Button click with the given x, y axis (w.r.t to the button), y axis value should be the height of the button:

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;

namespace ButtonDropDownTest
{
    public partial class Form1 : Form
    {
        private ContextMenuStrip _contextMenuAutoFill;

        public Form1()
        {
            InitializeComponent();
            CreateContextMenuStrip();
        }

        private void CreateContextMenuStrip()
        {
            _contextMenuAutoFill = new ContextMenuStrip();
            _contextMenuAutoFill.Items.Add("Dropdown item 1");
            _contextMenuAutoFill.Items.Add("Dropdown item 2");
            _contextMenuAutoFill.Items.Add("Dropdown item 3");
            _contextMenuAutoFill.Items.Add("Dropdown item 4");

            foreach (ToolStripMenuItem mItem in _contextMenuAutoFill.Items)
                mItem.Click += 
                new System.EventHandler(this.AutoFillToolStripMenuItem_Click);
        }

        private void button1_Click(object sender, EventArgs e)
        {
            button1.ContextMenuStrip = _contextMenuAutoFill;
            button1.ContextMenuStrip.Show
		(button1, new System.Drawing.Point(0, button1.Height));
        }

        private void AutoFillToolStripMenuItem_Click(object sender, EventArgs e)
        {
            string m = ((ToolStripMenuItem)sender).Text;
            MessageBox.Show("You have clicked '" + m + "'");
        }
    }
}