How to disable mousewheel for one control i.e. Combo Box?

Question

I have created an application that uses a combo box to select a user then display a database for that user. However when you scroll WITHOUT first clicking on the panel or datagridview it scrolls on the combo box there by selecting a different users database information I proceeded

this.cmbNetworkComputers.MouseWheel += new System.Windows.Forms.MouseEventHandler(this.cmbNetworkComputers_MouseWheel);

with

void cmbNetworkComputers_MouseWheel(object sender, MouseEventArgs e)
{
    ((HandledMouseEventArgs)e).Handled = true;
}

however these disable for my entire winform instead of just the combo box cmbNetwork computers HOW do you only disable the mouse wheel for ONLY one control

Answer 1

Add an event handler to your code

private void anycontrol_MouseEnter(object sender, System.EventArgs e) 
{
    var senderControl = sender as System.Windows.Forms.Control;
    if(senderControl==null)
        return;
    senderControl.Focus();
}

And assign it to any controls you want your focus to be applied automatically.

somePanel.MouseEnter += new System.EventHandler(anycontrol_MouseEnter);
//or this way
somePanel.MouseEnter += anycontrol_MouseEnter;
someComboBox.MouseEnter += anycontrol_MouseEnter;

edit:

Including the details you provided, I'd do it this way:

bool AllowUsersScrolling;
private void usersCombobox_MouseLeave(object sender, System.EventArgs e) 
{
    AllowUsersScrolling = false;
}
private void usersCombobox_MouseEnter(object sender, System.EventArgs e) 
{
    AllowUsersScrolling = true;
}
private void usersCombobox_MouseWheel(object sender, MouseEventArgs e)
{
    if(!AllowUsersScrolling)
        ((HandledMouseEventArgs)e).Handled = true;
}

And attach those handlers to your control's events respectively.

Answer 2

The MouseWheel event handler is not specific to a particular control, and instead applies to the whole form. This is likely why it doesn't show up the property grid for individual controls. You can opt-out any controls that shouldn't process the mouse wheel messages by checking the sender value against particular controls. This allows other controls to use the mouse wheel.

private void cboProfile_MouseWheel(object sender, MouseEventArgs e)
{
    if (sender == cboProfile)
    {
        ((HandledMouseEventArgs)e).Handled = true;
    }
}

Answer 3

I had the same problem as you, but I solved it this way:

private void strSearchBox_MouseWheel(object sender, MouseEventArgs e) {
  logList.TopIndex -= e.Delta;
  ((HandledMouseEventArgs)e).Handled = true;
}

Now the combobox scrolls for the list when the combobox is active. I think this is what you want, no?