private void btnDifference_Click(object sender, EventArgs e)
{
ITopologicalOperator2D topoOpera = geo1 as ITopologicalOperator2D;
if (topoOpera == null)
{
return;
}
IGeometry geo = topoOpera.Difference2D(geo2);
draw(geo);
}
private void btnDifference_Click(object sender, EventArgs e)
{
IGeometry p = polygonList[0];
for (int i = 0; i < polygonList.Count - 1; i++)
{
IPolygon piplus = polygonList[i + 1];
ITopologicalOperator2D topoOpera = p as ITopologicalOperator2D;
if (topoOpera == null)
{
continue;
}
p = topoOpera.Difference2D(piplus);
}
if (p.GeometryType == gviGeometryType.gviGeometryMultiPolygon)
{
_multiPolygon = p as IMultiPolygon;
}
else if (p.GeometryType == gviGeometryType.gviGeometryPolygon)
{
_multiPolygon.AddGeometry(p);
}
}