Figures

Figure 1

Connectionless Recordset



'==========================================================================
' NAME: DrivesRecordset.vbs
'
' COMMENT: Exposes drive information through an ADO recordset
'==========================================================================

' Constants
Const adUseClient = 3
Const adCurrency = 6
Const adBSTR = 8

' Local variables
Dim fso, rst, drives

' Creates the main objects of the script
Set fso = CreateObject("Scripting.FileSystemObject")
Set rst = CreateObject("ADODB.Recordset")

' Gets the collection of available drives
Set drives = fso.Drives

' Prepares the recordset structure: Root, Volume, Type, FileSystem, FreeSpace
rst.CursorLocation = adUseClient
rst.Fields.Append "Root", adBSTR
rst.Fields.Append "Volume", adBSTR
rst.Fields.Append "Type", adBSTR
rst.Fields.Append "FileSystem", adBSTR
rst.Fields.Append "FreeSpace", adCurrency
rst.Open

' Fills the recordset out with drive information
for each drv in drives 
    rst.AddNew
    if drv.IsReady then
        rst.Fields("Root").Value = drv.DriveLetter
        rst.Fields("Volume").Value = drv.VolumeName
        rst.Fields("Type").Value = drv.DriveType
        rst.Fields("FileSystem").Value = drv.FileSystem
        rst.Fields("FreeSpace").Value = drv.FreeSpace /1024
    end if 
next 

' Displays the recordset
s = ""
rst.MoveFirst
while Not rst.EOF
    for each fld in rst.Fields 
        s = s & Pad(rst.Fields(fld.Name), 14) & vbTab 
    next
    s = s & vbCrLf
    rst.MoveNext
wend

MsgBox s


'==========================================================================
' Pad(str, numChars)
' Pads the specified string with the specified trailing blanks
'==========================================================================
Function Pad (str, numChars)
    str = str & Space(numChars)
    Pad = Left(str, numChars)
End Function

Figure 3

Creating a JavaScript Object



'<SCRIPT RUNAT="SERVER" LANGUAGE="JavaScript">

//  JsRecordset.js 
//  Provides a JavaScript implementation of ADO recordsets


// Creates a new object with as many fields as specified
// INPUT: <fields> it's a reference to an ADO Fields object

function Record(fields)
{
    var i;
    
    // Add a new named property for each field in the recordset
    for (i=0; i<fields.Count; i++) {
        cmd = "this." + fields.Item(i).Name + " = \"" + 
              fields.Item(i).Name + "\"";
        eval(cmd);
    }
}


// Creates and fills a new array with as many records as the  
// specified ADO recordset 
// INPUT: <rst> it's a reference to an ADO recordset object
function Recordset(rst)
{
    // Define the Items property being the collection of records
    this.Items = new Array();
    
    var i=0;
    var cmd = "";
    
    // For each record in the recordset creates a Record object
    // and populates its properties with the values
    numOfFields = rst.Fields.Count;
    while (!rst.EOF) {
        this.Items[i] = new Record(rst.Fields);
        
        for (j=0; j<numOfFields; j++) 
        {
            cmd = "this.Items[i]." + rst.Fields.Item(j).Name + 
                  " = String(rst.Fields.Item(j).Value)"; 
            eval(cmd);  
        }        

        rst.MoveNext();
        i++;
    }
    
    // Define the length property counting the records
    this.length = i;
}

// Rebuilds the JavaScript Recordset object from a 
// serialized version of it. 
// INPUT: <string representing a serialized RS> 
function EvalRS(strRS)
{
    // The original string is in the form:
    //   <RETURN_VALUE...><METHOD...>
    //    var undefined; ...
    //   </RETURN_VALUE></METHOD>

    // Unescapes the original string
    strOriginal = unescape(strRS);
    
    // The string we're interested in begins with 'var 
    // undefined;'
    pos = strOriginal.indexOf("var");
    strRawData = strOriginal.substr(pos);
    
    // Removes the closing tags
    pos = strRawData.indexOf("</RETURN_VALUE></METHOD>");
    strRawData = strRawData.substring(0,pos);
    
    // Rebuilds the object and returns
    return eval(strRawData);
}
</SCRIPT>

Figure 5

Putting Fields into an Array



<SCRIPT LANGUAGE="javascript">

    var serverURL = "http://expoware";
    var pageURL   = "/mind/rs/server/EmpData2.asp";

    function refreshPage(co)
    {
        if (co.status == 0) {
            oRS = co.return_value;    
            if (oRS.length == 0) {
                empName.innerText = "";
                empCity.innerText = "";
                empTitle.innerText = "";
                empHired.innerText = "";
                errLog.value = "No record found.";
                return;
            }

            empName.innerText = oRS.Items[0].EmployeeID + 
                " - " + oRS.Items[0].TitleOfCourtesy + " " + 
                oRS.Items[0].FirstName + " " +    
                oRS.Items[0].LastName;
            empTitle.innerText = oRS.Items[0].Title;
            empCity.innerText = oRS.Items[0].City + " " + 
                                oRS.Items[0].Region + ", " + 
                                oRS.Items[0].Country; 
            d = new Date(oRS.Items[0].HireDate);
            empHired.innerText = (1+d.getMonth()) + "/" + 
                d.getDate() + "/" + d.getYear(); 
        }
    }
 
    function errHandler(co)
    {
        if (co.status != 0) 
            co.context.value = co.message;
    }

    function execCall()
    {
        errLog.value = "";
        var co = RSExecute(serverURL+pageURL,"GetEmployeeInfo", 
                           txtEmpName.value, 
                           refreshPage, errHandler, errLog);
    }
</SCRIPT>

Figure 6

Getting Specific Fields



<<%@ LANGUAGE=VBSCRIPT %>
<% RSDispatch %>

<SCRIPT RUNAT=SERVER Language="JScript">
<!--#INCLUDE VIRTUAL="/_ScriptLibrary/RS.ASP"-->
<!--#INCLUDE VIRTUAL="/_ScriptLibrary/JSRECORDSET.ASP"-->

    var adUseClient = 3;

    function Description()
    { 
        this.GetEmployeeInfo = DoGetEmployeeInfoAsRecordset;
    }
    public_description = new Description();


    function DoGetEmployeeInfoAsRecordset(empName)
    {
        sql = "select ";
        sql += "EmployeeID, FirstName, LastName, 
               TitleOfCourtesy, ";
        sql += "City, HireDate, Region, Country, Title ";
        sql += "from Employees where LastName='" 
        sql += empName + "'";
        rst = new ActiveXObject("ADODB.Recordset");
        rst.CursorLocation = adUseClient;

        rst.Open(sql, "NW");
        oRS = new Recordset(rst);
        rst.Close();
        return oRS; 
 }
</SCRIPT>
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