//构造切线点
private void button5_Click(object sender, EventArgs e)
{
delFeature("point");
IPoint[] points = new IPoint[4];
for (int i = 0; i < 4; i++)
{
points[i] = new PointClass();
}
points[0].PutCoords(15, 10);
points[1].PutCoords(20, 60);
points[2].PutCoords(40, 60);
points[3].PutCoords(45, 10);
addFeature("point", points[0]);
addFeature("point", points[1]);
addFeature("point", points[2]);
addFeature("point", points[3]);
IBezierCurveGEN bezierCurve = new BezierCurveClass();
bezierCurve.PutCoords(ref points);
IConstructMultipoint constructMultipoint = new MultipointClass();
constructMultipoint.ConstructTangent(bezierCurve as ICurve, points[1]);
IMultipoint multipoint = constructMultipoint as IMultipoint;
IPointCollection pointCollection = multipoint as IPointCollection;
for (int i = 0; i < pointCollection.PointCount; i++)
{
addFeature("point", pointCollection.get_Point(i));
}
axMapControl1.Refresh();
}
