Implementation of tree structure (II.)

Tree type Structure implementation of tree structure (Part II)
Author: ACE Last updated: 06/08/2000 Category: Original

In the previous section, we discussed how to read data and get a result set that represents a hierarchical relationship. In this section, let's look at how to implement an MSDN-like interface in scripting languages.

This functionality can be done on the server side as well as on the client, which depends on the need. The server-side completion requires the processing time of the server and related resources, the client is required to support scripting language (usually JavaScript), and to download the execution script.

In our example, we use the method of client-side script execution.

1. Send data to the browser

Look at the following code:

Dim getrsstring
Dim CNN
Dim RS
Dim l_id
l_id = "1" ' means root node

Set CNN = Server.CreateObject ("ADODB.") Connection ")
Set rs = Server.CreateObject ("ADODB.") RecordSet ")
Cnn. Open "Provider=sqloledb ................ Slightly
Rs. Open "Sp_listfile" & L_ID,CNN

getrsstring = Rs. GetString (2,, "quot;", "~ ~") ' adClipString
Rs. Close
Set rs = Nothing
Cnn. Close
Set cnn = Nothing

Response.Write "<form id= ' rs ' name= ' rs ' >" &_
"<input type= ' hidden ' id= ' rscache ' name= '" Rscache ' value= ' "" & Getrsstring & "' ></FORM>" &_
"<script language=javascript src= ' listfile.js ' ></SCRIPT>" &_
"<script language=javascript>loadrecords (" + l_id + ");</script>"

In the code above, a string separated by a quot and ~ ~ is obtained using the GetString method, and is stored with a hidden form. The Listfile.js script implements what we want, and Loadrecords is one of those functions.

2. Scripts in Listfile.js

This is all code:

function Toggledisplay (Obutton, Oitems)
{
if ((OItems.style.display = "") | |    (OItems.style.display = = "None")) {
OItems.style.display = "block";
OBUTTON.SRC = BOOK_OPEN.SRC;
} else {
OItems.style.display = "None";
OBUTTON.SRC = BOOK_CLOSE.SRC;
}

}
function Loadrecords (l_id) {
var strrecords=document.all ("Rscache"). Value;
var arrrecords=strrecords.split ("~ ~");
var arrfields;
var current_level;
var current_id;
var strtemp;
var strlist;
var prior_id;
var prior_level=-1;
var i;
var J;
prior_id=l_id;
Strlist = "<table><tr><td height=300 valign=top class=newscontents><!--" + L_ID + "-->";
for (i=0;i<arrrecords.length;i++)
{
Arrfields=arrrecords[i].split ("? quot;");
Current_level = Arrfields[0];
current_id = arrfields[1];
if (arrfields[2] = = 0)
{
strtemp = "<div><img src= ' http://www.163design.net/a/q/images/plus.gif ' id= ' i_" + current_id +
"' Position:relative;left:" + (CURRENT_LEVEL*17) +
&nb