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其实在revit里是不存在分割族的概念。
对于基于线形的族，截面沿线都是一样，要想达到分割的状态，只需要把族基于线的那条线变短，然后再在分割点复制一个新的族即可。
过程是先获得线的均分点，然后把族的线缩短，接着再复制族，即可变成均分的效果。主要方法见代码:
private void DevideFamilyInstance(FamilyInstance famIns,int n, Document revitDoc)
{
LocationCurve locationCurve = famIns.Location as LocationCurve;
XYZ stratPoint = locationCurve.Curve.GetEndPoint(0);
XYZ endPoint = locationCurve.Curve.GetEndPoint(1);
IList<XYZ> devidePoint = InsertPoint(stratPoint, endPoint,n);
Transaction transaction = new Transaction(revitDoc);
transaction.Start("将族复制到相应位置");
locationCurve.Curve = Line.CreateBound(stratPoint, devidePoint[0]);
List<ElementId> list = new List<ElementId>();
list.Add(famIns.Id);
ICollection<ElementId> elementIds = list;
for (int j=1;j<n;j++)
{
XYZ tanslation = new XYZ(devidePoint[j - 1].X - stratPoint.X, devidePoint[j - 1].Y - stratPoint.Y, devidePoint[j - 1].Z - stratPoint.Z);
ElementTransformUtils.CopyElements(revitDoc, elementIds, tanslation);
}
transaction.Commit();
}
private List<XYZ> InsertPoint(XYZ stratPoint, XYZ endPoint,int n)
{
List<XYZ> listPoint = new List<XYZ>();
double x, y, z;
for(int i=1;i<n;i++)
{
x = stratPoint.X+(endPoint.X- stratPoint.X)*i/n;
y = stratPoint.Y + (endPoint.Y - stratPoint.Y) * i / n;
z= stratPoint.Z + (endPoint.Z - stratPoint.Z) * i / n;
XYZ point = new XYZ(x,y,z);
listPoint.Add(point);
}