// Try to unregister the event handler and stop monitoring
private void btnStop_Click(object sender, EventArgs e)
{
if (lstMonitoringItems.SelectedItems.Count == 1)
{
MonitoringItem item = null;
MyEventViewer.MonitoringItems.TryGetValue(
lstMonitoringItems.SelectedItems[0].Text, out item);
if (item.State == MonitoringItemState.Running)
{
try
{
item.StopMonitoring();
item.WmiEventReceived -= MyEventViewer.HandleEvent;
UpdateQueryListView();
}
catch (Exception ex)
{
MessageBox.Show("Can not stop monitoring" +
" for the following reason:" +
Environment.NewLine + ex.Message);
}
}
}
}
// Clicking btnRemove should do two things:
// 1. Remove the selected element from the monitoredItems dictionary
// 2. Remove the selected element from the ListView
private void btnRemove_Click(object sender, EventArgs e)
{
if (lstMonitoringItems.SelectedItems.Count == 1)
{
MonitoringItem item = null;
MyEventViewer.MonitoringItems.TryGetValue(
lstMonitoringItems.SelectedItems[0].Name, out item);
item.StopMonitoring();
MyEventViewer.MonitoringItems.Remove(item.Name);
// Select the item after the one that got deleted
// If the last item is deleted select the new
// last item in the list
int deletedIndex =
lstMonitoringItems.SelectedItems[0].Index;
lstMonitoringItems.SelectedItems[0].Remove();
if (lstMonitoringItems.Items.Count > deletedIndex)
{
lstMonitoringItems.Items[deletedIndex].Selected = true;
}
else if (lstMonitoringItems.Items.Count > 1)
{
lstMonitoringItems.Items
[lstMonitoringItems.Items.Count - 1].Selected = true;
}
}
else
{
MessageBox.Show("Please select the monitoring item" +
" you want to delete");
}
}