Can I disable a combobox in WinForms without graying it out?

Is there a way to disable value change for a combo box without graying it out in windows forms? I saw a few posts but they开发者_运维知识库 were for WPF and didnt help my situation.

Setting these on your comobobox will do the trick you are looking for, Combo is enabled but nobody can change or type anything so Appearance = Enabled, Behaviour = Disabled :)

        comboBox1.DropDownHeight = 1;
        comboBox1.KeyDown += (s, e) => e.Handled = true;
        comboBox1.KeyPress += (s, e) => e.Handled = true;
        comboBox1.KeyUp += (s, e) => e.Handled = true;

If for some reason you cannot use lambdas then following handlers can be associated. Right Click -> Paste has to be handled additionally if you have DropDownStyle = DropDown.

    //void comboBox1_KeyUp(object sender, KeyEventArgs e)
    //{
    //    e.Handled = true;
    //}

    //void comboBox1_KeyPress(object sender, KeyPressEventArgs e)
    //{
    //    e.Handled = true;
    //}

    //void comboBox1_KeyDown(object sender, KeyEventArgs e)
    //{
    //    e.Handled = true;
    //}

Fantius' solution is a really good one, I've found out, but since I'm a newbie here, I can't comment on it. But as this question was the first Google hit, it seemed useful to add this even though I'm 11 years late:

Setting the focus to the next control in the Enter handler, makes the ComboBox entirely resistant to clicks and is exactly what I needed.

The comboBox1.DropDownHeight = 1; in the accepted answer shows a weird one-pixel dropdown that looks kinda broken to my UI-sensitive eyes.

The only disadvantage I've found is that one can't Shift-Tab across the field but in my case that's not a problem.

Then save his handlers as variables and simply -= them after.

Example:

var keyDown = (s, e) => e.Handled = true;
var keyPress = (s, e) => e.Handled = true;
var keyUp = (s, e) => e.Handled = true;

Then replace in his with:

comboBox1.KeyDown += keyDown;
comboBox1.KeyPress += keyPress;
comboBox1.KeyUp += keyUp;

Then when you want to remove:

comboBox1.KeyDown -= keyDown;
comboBox1.KeyPress -= keyPress;
comboBox1.KeyUp -= keyUp;

In the GotFocus hander (whatever it is called), set the focus to something else.

Nah, not good enough. Make it disabled and look exactly like the original so the user is completely fooled. Add a new class and paste this code.

using System;
using System.Drawing;
using System.Windows.Forms;

class FakeComboBox : ComboBox {
    private PictureBox fake;
    public new bool Enabled {
        get { return base.Enabled; }
        set { if (!this.DesignMode) displayFake(value);
              base.Enabled = value;
        }
    }
    private void displayFake(bool enabled) {
        if (!enabled) {
            fake = new PictureBox();
            fake.Location = this.Location;
            fake.Size = this.Size;
            var bmp = new Bitmap(fake.Size.Width, fake.Size.Height);
            this.DrawToBitmap(bmp, new Rectangle(0, 0, bmp.Width, bmp.Height));
            fake.Image = bmp;
            this.Parent.Controls.Add(fake);
            fake.BringToFront();
            fake.Click += delegate { Console.Beep(); };
        }
        else {
            this.Parent.Controls.Remove(fake);
            fake.Dispose();
            fake = null;
        }
    }
}

The very slight 'glow' you get on Win7 when you re-enable it is very interesting.