DataGridView多维表头的实现方法(3)

之所以要对GridView中原始的列头进行特别处理，是因为这里的起止坐标和终止坐标都可以设置，而原始列头的起始纵坐标（StartY）只能是0，终止横坐标（EndX）必须与起始横坐标（StartY）相等。

另外所有列头单元格的集合HeaderCollection的定义如下

复制代码 代码如下:

public class HeaderCollection
     {
         private List<HeaderItem> _headerList;
         private bool _iniLock;

         public DataGridViewColumnCollection BindCollection{get;set;}

         public HeaderCollection(DataGridViewColumnCollection cols)
         {
             _headerList = new List<HeaderItem>();
             BindCollection=cols;
             _iniLock = false;
         }

         public int GetHeaderLevels()
         {
             int max = 0;
             foreach (HeaderItem item in _headerList)
                 if (item.EndY > max)
                     max = item.EndY;

             return max;
         }

         public List<HeaderItem> GetBaseHeaders()
         {
             List<HeaderItem> list = new List<HeaderItem>();
             foreach (HeaderItem item in _headerList)
                 if (item.IsBaseHeader) list.Add(item);
             return list;
         }

         public HeaderItem GetHeaderByLocation(int x, int y)
         {
             if (!_iniLock) InitHeader();
             HeaderItem result=null;
             List<HeaderItem> temp = new List<HeaderItem>();
             foreach (HeaderItem item in _headerList)
                 if (item.StartX <= x && item.EndX >= x)
                     temp.Add(item);
             foreach (HeaderItem item in temp)
                 if (item.StartY <= y && item.EndY >= y)
                     result = item;

             return result;
         }

         public IEnumerator GetHeaderEnumer()
         {
             return _headerList.GetEnumerator();
         }

         public void AddHeader(HeaderItem header)
         {
             this._headerList.Add(header);
         }

         public void AddHeader(int startX, int endX, int startY, int endY, string content)
         {
             this._headerList.Add(new HeaderItem(startX,endX,startY,endY,content));
         }

         public void AddHeader(int x, int y, string content)
         {
             this._headerList.Add(new HeaderItem(x, y, content));
         }

         public void RemoveHeader(HeaderItem header)
         {
             this._headerList.Remove(header);
         }

         public void RemoveHeader(int x, int y)
         {
            HeaderItem header= GetHeaderByLocation(x, y);
            if (header != null) RemoveHeader(header);
         }

         private void InitHeader()
         {
             _iniLock = true;
             for (int i = 0; i < this.BindCollection.Count; i++)
                 if(this.GetHeaderByLocation(i,0)==null)
                 this._headerList.Add(HeaderItem.CreateBaseHeader(i,0 , this.BindCollection[i].HeaderText));
             _iniLock = false;
         }
     }

这里仿照了.NET Frameword的Collection那样定义了Add方法和Remove方法，此外说明一下那个 GetHeaderByLocation 方法，这个方法可以通过给定的坐标获取那个坐标的HeaderItem。这个坐标是忽略了整个表头合并单元格的情况，例如

上面这幅图，如果输入0，0 返回的是灰色区域，输入2，1 或3，2 或 5，1返回的都是橙色的区域。

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