Asp. NET to generate a tree-shaped display of the GridView implementation of the idea _ practical skills

Objective: To generate tabular data for the tree structure (Easyui also has treegrid, here is just a thought) to extend the click expand/Shrink Node
Legend:

Class Code:

Copy Code code as follows:

Using System;
Using System.Data;
<summary>
Summary description of Gridviewhelper
</summary>
public class Gridviewhelper
{
private string gridline; Connecting lines
Private DataTable DT; Incoming DataTable
Private DataTable dtout; The Output DataTable
Private DataRow Row; Used to fetch data from DataView and increase it to dtout
Public Gridviewhelper ()
{
//
TODO: Add constructor logic here
//
}
<summary>
A DataTable that produces a tree structure
</summary>
<param name= "DataTable" > Raw datasheet </param>
<param name= "ParentField" > Parent node key field </param>
<param name= "Parentvalue" > Parent node Value </param>
<param name= "Keyfield" > This node key field </param>
<param name= "TextField" > Display text fields </param>
<param name= "sortstring" > Sort string </param>
The datatable</returns> after <returns> treatment
Public DataTable Getgridviewtreedata (DataTable DataTable, String ParentField, String parentvalue, String Keyfield, String TextField, String sortstring)
{
DataTable. Columns.Add ("Level", Type.GetType ("System.Int32"));
DT = DataTable;
Dtout = DataTable. Clone ();
Resettextfield (ParentField, Parentvalue, Keyfield, TextField, sortstring, 0);
return dtout;
}
<summary>
Recursive generation of new node names (with connecting wiring)
</summary>
<param name= "Parentvaluefield" > Parent node key field </param>
<param name= "Parentvalue" > Parent node Value </param>
<param name= "Keyfield" > This node key field </param>
<param name= "TextField" > Display text fields </param>
<param name= "sortstring" > Sort string </param>
<param name= "Level" > Tree depth </param>
<returns></returns>
private void Resettextfield (String Parentvaluefield, String parentvalue, String Keyfield, String TextField, String sortst Ring,int level)
{
DataView dv = new DataView (DT, Parentvaluefield + "= '" + Parentvalue + "" ", Sortstring, DataViewRowState.CurrentRows);
int a = DV. Count;
if (DV. Count = 0)
{
Return
}
for (int i = 0; i < A; i++)
{
gridline = "";
Dv. RowFilter = Parentvaluefield + "= '" + parentvalue + "'";
Dv. Sort = sortstring;
Gettreeline (Parentvaluefield, Dv[i][parentvaluefield). ToString (), Keyfield, Dv[i][keyfield]. ToString (), sortstring);
Dv. RowFilter = Parentvaluefield + "= '" + parentvalue + "'";
Dv. Sort = sortstring;
row = Dtout.newrow ();
for (int c = 0; c < dv[i]. Row.ItemArray.Length; C + +)
{
ROW[C] = Dv[i][c];
}
DTOUT.ROWS.ADD (row);
Dtout.rows[dtout.rows.count-1][textfield] = gridline + (i = = A-1? "┗": "Out") + Dv[i][textfield]. ToString ();
Dtout.rows[dtout.rows.count-1]["level"] = level;
Resettextfield (Parentvaluefield, Dv[i][keyfield). ToString (), Keyfield, TextField, sortstring,level+1);
}
Dv. Dispose ();
}
<summary>
A connection line that backtracking spanning a tree
</summary>
<param name= "Parentvaluefield" > Parent node key field </param>
<param name= "Parentvalue" > Parent node Value </param>
<param name= "Keyfield" > This node key field </param>
<param name= "Nodekey" > This node value </param>
<param name= "sortstring" > Sort string </param>
<returns></returns>
private void Gettreeline (String Parentvaluefield, String parentvalue, String Keyfield, String Nodekey, String sortstring)
{
Select Parent Layer Node
DataView dv = new DataView (DT, Keyfield + "= '" + Parentvalue + "" ", Sortstring, DataViewRowState.CurrentRows);
if (DV. Count > 0)
{
Select parent node Sibling node
Dv. RowFilter = Parentvaluefield + "= '" + Dv[0][parentvaluefield]. ToString () + "'";
Dv. Sort = sortstring;
for (int j = 0; J < DV.) Count; J + +)
{
if (Dv[j][keyfield). ToString () = = Parentvalue)
{
if (j = = dv. COUNT-1)
{
Gridline = "" + Gridline;
}
Else
{
Gridline = "┃" + gridline;
}
}
}
Gettreeline (Parentvaluefield, Dv[0][parentvaluefield). ToString (), Keyfield, Dv[0][keyfield]. ToString (), sortstring);
}
Dv. Dispose ();
}
}

HTML Sample code:

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<%@ Page language= "C #" autoeventwireup= "true" codefile= "GridViewTree.aspx.cs" inherits= "Gridviewtree"%>
<! DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 transitional//en" "Http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd ">
<title> generating a tree-shaped display of gridview</title>
<style type= "Text/css" >
Body
{
line-height:16px;
font-size:14px;
}
Td
{
padding:0 2px;
}
</style>
<body>
<form id= "Form1" runat= "Server" >
<table>
<tr>
&LT;TD valign= "Top" >
<asp:dropdownlist id= "DropDownList1" runat= "Server" >
</asp:DropDownList>
</td>
<td>
<asp:gridview id= "GridView1" runat= "Server" borderwidth= "1px" cellpadding= "3" gridlines= "Vertical"
autogeneratecolumns= "False" backcolor= "white" bordercolor= "#E7E7FF" borderstyle= "None" >
<alternatingrowstyle backcolor= "#F7F7F7"/>
<Columns>
<asp:boundfield datafield= "Context" headertext= "text"/>
<asp:boundfield datafield= "id" headertext= "id" >
<itemstyle horizontalalign= "Right" width= "80px"/>
</asp:BoundField>
<asp:boundfield datafield= "ParentID" headertext= "Parent ID" >
<itemstyle horizontalalign= "Right" width= "80px"/>
</asp:BoundField>
<asp:boundfield datafield= "Level" headertext= "level" >
<itemstyle horizontalalign= "Right" width= "80px"/>
</asp:BoundField>
</Columns>
<footerstyle backcolor= "#B5C7DE" forecolor= "#4A3C8C"/>
<pagerstyle backcolor= "#E7E7FF" forecolor= "#4A3C8C" horizontalalign= "right"/>
<rowstyle backcolor= "#E7E7FF" forecolor= "#4A3C8C"/>
<selectedrowstyle backcolor= "#738A9C" font-bold= "True" forecolor= "#F7F7F7"/>
<sortedascendingcellstyle backcolor= "#F4F4FD"/>
<sortedascendingheaderstyle backcolor= "#5A4C9D"/>
<sorteddescendingcellstyle backcolor= "#D8D8F0"/>
<sorteddescendingheaderstyle backcolor= "#3E3277"/>
</asp:GridView>
</td>
</tr>
</table>
</form>
</body>

Background code:

Copy Code code as follows:

DataTable dt = Gvhelper.getgridviewtreedata (DataTable, "ParentID", "1", "ID", "context", "context ASC");
Gridview1.datasource = DT;
Gridview1.databind ();
DropDownList1.Items.Add ("");
Dropdownlist1.appenddatabounditems = true;
Dropdownlist1.datasource = DT;
Dropdownlist1.datatextfield = "context";
Dropdownlist1.datavaluefield = "ID";
Dropdownlist1.databind ();