asp.net realization of dropdownlist,treeview,listbox infinite Pole Classification Tree _ Practical Skills

This article describes the infinite Polar classification tree of asp.net implementation dropdownlist,treeview,listbox. Share to everyone for your reference, specific as follows:

#region DropDownList infinite recursive display hierarchy///<summary>///create an infinite rating drop-down list box///</summary>///<param name= "Ddlst" > Dropdown Control </param>///<param name= "DT" > Source datatable</param>///<param name= "text" >text field </param >///<param name= "value" >value field </param>///<param name= "ParentID" > Depth field for example Parentid</param
> public static void Createleveldropdown (DropDownList ddlst, DataTable dt, string text, string value, String parentid)
  {ArrayList AllItems = new ArrayList (); datarow[] rows = dt.
  Select (parentid + "= 0"); foreach (DataRow row in rows) createleveldropdownassistant (DT, ref allitems, Row, string.
  Empty, text, value, ParentID);
  listitem[] items = new Listitem[allitems.count];
  Allitems.copyto (items); Ddlst.
Items.addrange (items); ///<summary>///Recursive binding sub-node///</summary>///<param name= "DT" > Source datatable</param>///-<param N Ame= "items" > Array </param>///<param name= "ParentRow" > Current node &LT;/PARAM&GT <param name= "Curheader" > Prefix </param>///<param name= "text" >text field </param>///<param Name= "Value" >value field </param>///<param name= "parentid" > depth fields such as parentid</param> private static void Createleveldropdownassistant (DataTable dt, ref ArrayList items, DataRow parentrow, String curheader, string text, St Ring value, String parentid) {ListItem newitem = new ListItem (Curheader + until.cutstring (parentrow[text). ToString (), true), Parentrow[value].
  ToString ()); Items.
  ADD (NewItem); datarow[] rows = dt.
  Select (parentid + "=" + Newitem.value); for (int i = 0; i < rows. Length-1; i++) createleveldropdownassistant (DT, ref items, Rows[i], Curheader.replace ("Out", "┃").
  Replace ("┗", "out") + "Out", text, value, ParentID); If rows. Length > 0) createleveldropdownassistant (DT, ref items, Rows[rows. Length-1], Curheader.replace ("Out", "┃").
Replace ("┗", "out") + "┗", text, value, ParentID); #endregion #region TreeView Infinite recursive display hierarchical relation meshRecord Tree///<summary>///Create an infinite hierarchical directory tree treeview///</summary>///<param name= "treeview" >treeview Space </param >///<param name= "DT" > Data source datatable</param>///<param name= "text" >text field </param>///< param name= "value" >value field </param>///<param name= "parentid" > depth fields such as parentid</param> public static void Createleveltreeview (TreeView treeview, DataTable DT, string text, string value, String parentid) {DataView DV = dt.
  DefaultView; Dv.
  RowFilter = parentid + "= 0";
    foreach (DataRowView drv in DV) {TreeNode node = new TreeNode (); Node. Text = Drv[text].
    ToString (); Node. Value = Drv[value].
    ToString (); Node.
    Expanded = false; Treeview.
    Nodes.Add (node);
  Creattreeviewchildnode (DV, node, text, value, ParentID); }///<summary>///recursive binding child node///</summary>///<param name= "DV" > Source dataview</param>///<param Name= "ParentNode" > Current node </param>///<param name= "text" >text Field </param>///<param name= "value" >value field </param>///<param name= "ParentID" > Depth field for example parentid</ param> private static void Creattreeviewchildnode (DataView dv, TreeNode parentnode, string text, String value, String p Arentid) {dv.
  RowFilter = parentid + "=" + Parentnode.value;
    foreach (DataRowView row in DV) {TreeNode Replynode = new TreeNode (); Replynode.text = Row[text].
    ToString (); Replynode.value = Row[value].
    ToString ();
    replynode.expanded = false;
    PARENTNODE.CHILDNODES.ADD (Replynode);
  Creattreeviewchildnode (DV, Replynode, text, value, ParentID); }///<summary>///create an infinite hierarchical directory tree treeview///</summary>///<param name= "treeview" >treeview Space </param >///<param name= "DT" > Data source datatable</param>///<param name= "text" >text field </param>///< param name= "value" >value field </param>///<param name= "url" >url field </param>///<param name= " ParentID > Depth fields such as Parentid</param> public static void Createleveltreeview (TreeView treeview, DataTable DT, string text, string value, string URL, string pare Ntid) {DataView dv = dt.
  DefaultView; Dv.
  RowFilter = parentid + "= 0";
    foreach (DataRowView drv in DV) {TreeNode node = new TreeNode (); Node. Text = Drv[text].
    ToString (); Node. Value = Drv[value].
    ToString (); Node. NavigateUrl = Drv[url].
    ToString (); Node.
    Expanded = false; Treeview.
    Nodes.Add (node);
  Creattreeviewchildnode (DV, node, text, value, URL, parentid); }///<summary>///recursive binding child node///</summary>///<param name= "DV" > Source dataview</param>///<param Name= "ParentNode" > Current node </param>///<param name= "text" >text field </param>///<param name= "value" >value field </param>///<param name= "url" >url field </param>///<param name= "ParentID" > Depth field For example parentid</param> private static void Creattreeviewchildnode (DataView dv, TreeNode parentnode, string text, String value, StRing URL, string parentid) {dv.
  RowFilter = parentid + "=" + Parentnode.value;
    foreach (DataRowView row in DV) {TreeNode Replynode = new TreeNode (); Replynode.text = Row[text].
    ToString (); Replynode.value = Row[value].
    ToString (); Replynode.navigateurl = Row[url].
    ToString ();
    replynode.expanded = false;
    PARENTNODE.CHILDNODES.ADD (Replynode);
  Creattreeviewchildnode (DV, Replynode, text, value, URL, parentid); #endregion #region Create an infinite hierarchical listbox///<summary>///Create an infinite hierarchical listbox///</summary>///<param name= "Ddlst" >listbox control </param>///<param name= "DT" > Source datatable</param>///<param the "text" name= field </param>///<param name= "value" >value field </param>///<param name= "ParentID" > Depth field for example ParentID </param> public static void Createlevellistbox (ListBox ddlst, DataTable dt, string text, String value, string parent
  ID) {ArrayList allitems = new ArrayList (); datarow[] rows = dt. Select (ParentiD + "= 0"); foreach (DataRow row in rows) createlevellistboxassistant (DT, ref allitems, Row, string.
  Empty, text, value, ParentID);
  listitem[] items = new Listitem[allitems.count];
  Allitems.copyto (items); Ddlst.
Items.addrange (items); ///<summary>///Recursive binding sub-node///</summary>///<param name= "DT" > Source datatable</param>///-<param N Ame= "items" > Array </param>///<param name= "ParentRow" > Current node </param>///<param name= "Curheader" > Prefix </param>///<param name= "text" >text field </param>///<param name= "value" >value field </ param>///<param name= "parentid" > depth fields such as parentid</param> private static void Createlevellistboxassistant (DataTable DT, ref ArrayList items, DataRow parentrow, String curheader, string text, String V Alue, String parentid) {ListItem newitem = new ListItem (Curheader + until.cutstring (parentrow[text). ToString (), true), Parentrow[value].
  ToString ()); Items.
  ADD (NewItem); Datarow[]rows = dt.
  Select (parentid + "=" + Newitem.value); for (int i = 0; i < rows. Length-1; i++) createlevellistboxassistant (DT, ref items, Rows[i], Curheader.replace ("Out", "┃").
  Replace ("┗", "out") + "Out", text, value, ParentID); If rows. Length > 0) createlevellistboxassistant (DT, ref items, Rows[rows. Length-1], Curheader.replace ("Out", "┃").
Replace ("┗", "out") + "┗", text, value, ParentID);

 } #endregion

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