CAD修改图块插入点到中心点（com接口）

主要用到函数说明：

IMxDrawEntity::GetBoundingBox

返回实体的最小矩形框外包。详细说明如下：

c#中实现代码说明：

//返回控件的数据库对象

MxDrawDatabase databae = (MxDrawDatabase)axMxDrawX1.GetDatabase();

//返回数据库中的块表对象

MxDrawBlockTable blkTab = databae.GetBlockTable();

//创建一个遍历块表中所有记录的遍历器

MxDrawBlockTableIterator mBlockTableiter = blkTab.NewIterator();

//移动当前遍历器位置

for (; !mBlockTableiter.Done(); mBlockTableiter.Step())

 

{

    //返回遍历器当前位置的记录

    MxDrawBlockTableRecord blkRec = mBlockTableiter.GetRecord();

    //创建一个遍历块表中所有记录的遍历器

    MxDrawBlockTableRecordIterator mBlockTableReciter = blkRec.NewIterator();

 

    MxDrawPoint mMaxPt = new MxDrawPoint();

    MxDrawPoint mMinPt = new MxDrawPoint();

 

    MxDrawPoint mMaxPtTemp = new MxDrawPoint();

    MxDrawPoint mMinPtTemp = new MxDrawPoint();

    //移动当前遍历器位置

    for (; !mBlockTableReciter.Done(); mBlockTableReciter.Step(true, false))

    {

        //与用户交互在图面上选择一个实体

        MxDrawEntity ent = mBlockTableReciter.GetEntity();

        //返回实体的最小矩形框外包

        ent.GetBoundingBox(out mMinPtTemp, out mMaxPtTemp);

 

        if ((mMinPtTemp == null) || (mMaxPtTemp == null))

            break;

 

        mMaxPt.x = Math.Max(mMaxPt.x, mMaxPtTemp.x);

        mMaxPt.y = Math.Max(mMaxPt.y, mMaxPtTemp.y);

 

        mMinPt.x = Math.Min(mMinPt.x, mMinPtTemp.x);

        mMinPt.y = Math.Min(mMinPt.y, mMinPtTemp.y);

 

    }

 

    if ((mMinPtTemp == null) || (mMaxPtTemp == null))

        continue;

 

    MxDrawPoint mNewBasePt = new MxDrawPoint();

 

    mNewBasePt.x = mMinPt.x + (mMaxPt.x - mMinPt.x) / 2;

    mNewBasePt.y = mMinPt.y + (mMaxPt.y - mMinPt.y) / 2;

    //块表记录的插入原点属性

    blkRec.Origin = mNewBasePt;

    //重新生成图，重新生成所有显示数据

    axMxDrawX1.Regen();

}