private void maketree(datatable dtnodesets, string strparentcolumn, string strrootvalue, string strindexcolumn, string strtextcolumn, dropdownlist drpbind, int i) { //每向下一层，多一个缩入单位   i++; dataview dvnodesets = new dataview(dtnodesets); dvnodesets.rowfilter = strparentcolumn + "=" + strrootvalue; string strpading = ""; //缩入字符  //通过i来控制缩入字符的长度，我这里设定的是一个全角的空格   for (int j = 0; j < i; j++) strpading += "　";//如果要增加缩入的长度，改成两个全角的空格就可以了  foreach (datarowview drv in dvnodesets) { treenode tnnode = new treenode(); listitem li = new listitem(strpading + "├" + drv[strtextcolumn].tostring(), drv[strindexcolumn].tostring()); drpbind.items.add(li); maketree(dtnodesets, strparentcolumn, drv[strindexcolumn].tostring(), strindexcolumn, strtextcolumn, drpbind, i); } //递归结束，要回到上一层，所以缩入量减少一个单位   i--; } /// <summary>   /// sql语句查询，再绑定到droplist里面   /// </summary>   private void createtree() { //查询zonelist   string sql = "select * from master_department where parent_department='003'"; dataset ds = db.getds(); datatable dt = ds.tables[0]; maketree(dt, "parent_department", "003", "department_code", "department_name", dropdownlist1, -1); }

using system; using system.collections.generic; using system.text; using system.web.ui.webcontrols; namespace interface.common {     public interface idropdowntree : idisposable     {         /**//// <summary>         /// 返回dictionary里分别对应id,文本,如果没有子节点返回null         /// </summary>         /// <param name="parentid">父节点id</param>         /// <returns></returns>         dictionary<string, string> getchildcategory(string parentid);         /**//// <summary>         /// 代码里写return new interface.common.dropdowntree(this);         /// </summary>         dropdowntree dropdowntree         {             get;         }     }     public sealed class dropdowntree     {         idropdowntree _dropdowntree;         public dropdowntree(idropdowntree dropdowntree)         {             _dropdowntree = dropdowntree;         }         /**//// <summary>         /// 用于树的前缀         /// </summary>         /// <param name="islast">是否是同级节点中的最后一个</param>         /// <param name="haschild">本节点是否拥有子节点</param>         /// <param name="parentstring">父节点前缀符号</param>         /// <returns>本节点的前缀</returns>         private string getprefix(bool islast, bool haschild, string parentstring)         {             string result = string.empty;             if (!string.isnullorempty(parentstring))             {                 parentstring = parentstring.remove(parentstring.length - 1).replace("├", "│").replace("└", "　");                 result += parentstring;             }             if (islast)             {                 result += "└";             }             else             {                 result += "├";             }             if (haschild)             {                 result += "┬";             }             else             {                 result += "─";             }             return result;         }         绑定下拉菜单#region 绑定下拉菜单         /**//// <summary>         /// 绑定连动级的下拉菜单         /// </summary>         /// <param name="ddlgoodstype">传进一个被绑定的dropdownlist</param>         /// <param name="removeid">被排除绑定的节点id</param>         /// <param name="autodispose">是否自动释放</param>         public void bindtodropdownlist(dropdownlist ddlgoodstype, string removeid,string parentid, bool autodispose)         {             if (ddlgoodstype != null)             {                 listitem listitem = null;                 string currentid = parentid;//根节点/父id                 string currentsign = string.empty;//当前节点符号;                 string parrentsign = string.empty; //父节点符号;                 bool haschild = true;//是否有子                 queue<string> parentkeylist = new queue<string>();//存 有子节点的 节点id                 queue<string> parentsignlist = new queue<string>();//对应节点id的前缀符号                 int itemindexof = 0;//父节点所在的位置　                 while (haschild)                 {                     int lastonecount = 1;//用于计算在同级别中是否最后一个                     dictionary<string, string> childlist = _dropdowntree.getchildcategory(currentid);// 得到子节点列表                     if (childlist != null && childlist.count > 0)                     {                         if (!string.isnullorempty(removeid) && childlist.containskey(removeid))                         {                             childlist.remove(removeid);                         }                         foreach (keyvaluepair<string, string> entry in childlist)                         {                             if (_dropdowntree.getchildcategory(entry.key) != null)//存在子                             {                                 currentsign = getprefix(lastonecount == childlist.count, true, parrentsign);                                 listitem = new listitem(currentsign + entry.value, entry.key);                                 parentkeylist.enqueue(entry.key);//当前的节点id                                 parentsignlist.enqueue(currentsign);//当前的节点符号                             }                             else//不存在子                             {                                 currentsign = getprefix(lastonecount == childlist.count, false, parrentsign);                                 listitem = new listitem(currentsign + entry.value, entry.key);                             }                             if (ddlgoodstype.items.count != 0)                             {                                 itemindexof = string.isnullorempty(currentid) ? itemindexof + 1 : ddlgoodstype.items.indexof(ddlgoodstype.items.findbyvalue(currentid)) + lastonecount;                             }                             ddlgoodstype.items.insert(itemindexof, listitem);//添加子节点                             lastonecount++;                         }                         if (parentkeylist.count > 0)//存在子节点时                         {                             currentid = parentkeylist.dequeue();                             parrentsign = parentsignlist.dequeue();                         }                         else                         {                             haschild = false;                         }                     }                     else                     {                         break;                     }                 }                 if (autodispose)                 {                     _dropdowntree.dispose();                 }             }         }         /**//// <summary>         /// 绑定连动级的下拉菜单         /// </summary>         /// <param name="ddlgoodstype">传进一个被绑定的dropdownlist</param>         public void bindtodropdownlist(dropdownlist ddlgoodstype)         {             bindtodropdownlist(ddlgoodstype, string.empty,null, true);         }         /**//// <summary>         /// 绑定连动级的下拉菜单         /// </summary>         /// <param name="ddlgoodstype">传进一个被绑定的dropdownlist</param>         /// <param name="removeid">被排除的id</param>         public void bindtodropdownlist(dropdownlist ddlgoodstype, string removeid)         {             bindtodropdownlist(ddlgoodstype, removeid,null, true);         }         /**//// <summary>         /// 绑定连动级的下拉菜单         /// </summary>         /// <param name="ddlgoodstype">传进一个被绑定的dropdownlist</param>         /// <param name="removeid">被排除的id,若没有,传null</param>         /// <param name="parentid">起始父id</param>         public void bindtodropdownlist(dropdownlist ddlgoodstype, string removeid,string parentid)         {             bindtodropdownlist(ddlgoodstype, removeid,parentid, true);         }         #endregion     } }

idropdowntree 成员 #region idropdowntree 成员 public dictionary<string, string> getchildcategory(string parentid) {     string where = "parentid='" + parentid + "'";     if (string.isnullorempty(parentid))     {  where = "parentid is null or parentid='" + guid.empty + "'";     }     list<goodscategorybean> _goodscategorylist = selectlist(0, where, string.empty, false);     if (_goodscategorylist != null && _goodscategorylist.count > 0)     {  dictionary<string, string> categorylist = new dictionary<string, string>();  for (int i = 0; i < _goodscategorylist.count; i++)  {      categorylist.add(_goodscategorylist[i].id.tostring(), _goodscategorylist[i].gategoryname);  }  return categorylist;     }//51aspx.com     return null; } public interface.common.dropdowntree dropdowntree {     get { return new interface.common.dropdowntree(this); } } #endregion