private void toolStripMenuItemDiagramAlignMiddle_Click(object sender, EventArgs e)
{
foreach (DocDefinition docDef in this.ctlExpressG.Multiselection)
{
DocDefinition docSel = ((DocDefinition)this.ctlExpressG.Selection);
docDef.DiagramRectangle.Y = docSel.DiagramRectangle.Y + docSel.DiagramRectangle.Height * 0.5 - docDef.DiagramRectangle.Height * 0.5;
this.ctlExpressG.LayoutDefinition(docDef);
}
this.ctlExpressG.Redraw();
}