Detecting Mouse Button Events in C#


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This is a simple program I wrote when I needed to detect the right mouse button click in a listbox and couldn't find it in the VS.NET IDE. In the documentation I came across a class called "MouseEventArgs".

MouseEventArgs is passed to a MouseEventHandler defined for the listbox. In the InitializeComponent() method for the form is the definition and initialization of the components of the form. I added The following to this section:

this.m_listbox.MouseDown += new System.Windows.Forms.MouseEventHandler(this.ButtonDown);

This sets the method ButtonDown to receive all mouse button events. There I determine what button was pressed, what row was clicked on, and display the results. The only events I see useful are left, right, and middle. Microsoft added two more events, XButton1 and XButton2, for it's own devices. The documentation even has a 'none' event, which I cannot fathom. That's about it.

private void OKButtonClick(object sender, System.EventArgs e)
private void ButtonDown(object sender, MouseEventArgs mea)
   int nDx = 0; //This will be the 0 based index of the row clicked on
    if (mea.Button == MouseButtons.Right) { //Check for right button click
        m_mouse_event.Text = "Right Button Clicked\r\n";
    else if (mea.Button == MouseButtons.Left) { //Check for Left button click
        m_mouse_event.Text = "Left Button Clicked\r\n";
    nDx = mea.Y / m_listbox.ItemHeight; //Get Index of item selected
    m_mouse_event.Text = m_mouse_event.Text +
            "Item height = " + m_listbox.ItemHeight.ToString()+ "\r\n" +
            "X position = " + mea.X.ToString() + "\r\n" +
            "Y position = " + mea.Y.ToString() + "\n" +"\r\n"+
            "Index = " + nDx.ToString();
    if ( m_listbox.Items.Count <= nDx ) m_mouse_event.Text = m_mouse_event.Text + "\r\n" +
            "Row Clicked Beyond Table size";
    else m_listbox.SetSelected(nDx,true);         //highlight row selected



Download demo project - 79 Kb
Download source - 8 Kb