private void mnuHoverVal_Click(Object sender, EventArgs e)
{
MenuItem _item = (MenuItem)sender;
Canvas _graph = (Canvas)_item.Tag;
plotData _plotData = getPlotData((string)_graph.Tag);
Canvas _plotarea = _plotData.plotarea;
_plotData.displayHoverVal = !_plotData.displayHoverVal;
_item.IsChecked = _plotData.displayHoverVal;
if (!_plotData.displayHoverVal)
{
_plotData.hoverVal.Text = "";
_plotData.hoverValBG.Text = "";
}
}