Real-Time Chart with Snapshot (Web)

[Web Version (in ASP)] aspdemo\realtimesnapshot.asp
<%@ language="vbscript" %>
<%
Set cd = CreateObject("ChartDirector.API")

'
' Data to draw the chart. In this demo, the data buffer will be filled by a random data generator.
' In real life, the data is probably stored in a buffer (eg. a database table, a text file, or some
' global memory) and updated by other means.
'

' We use a data buffer to emulate the last 240 samples.
sampleSize = 240
ReDim dataSeries1(sampleSize - 1)
ReDim dataSeries2(sampleSize - 1)
ReDim dataSeries3(sampleSize - 1)
ReDim timeStamps(sampleSize - 1)

' Our pseudo random number generator
firstDate = DateAdd("s", -(UBound(timeStamps) + 1), Now)
For i = 0 To UBound(timeStamps)
    timeStamps(i) = DateAdd("s", i, firstDate)
    p = Second(timeStamps(i)) + Minute(timeStamps(i)) * 60 + Hour(timeStamps(i)) * 3600
    dataSeries1(i) = Cos(p * 2.1) * 10 + 1 / (Cos(p) * Cos(p) + 0.01) + 20
    dataSeries2(i) = 100 * Sin(p / 27.7) * Sin(p / 10.1) + 150
    dataSeries3(i) = 100 * Cos(p / 6.7) * Cos(p / 11.9) + 150
Next

' Create an XYChart object 600 x 320 pixels in size
Set c = cd.XYChart(600, 320)

' Set the plotarea at (55, 60) and of size 520 x 235 pixels with transparent background and border.
' Enable both horizontal and vertical grids by setting their colors to grey (cccccc). Set clipping
' mode to clip the data lines to the plot area.
Call c.setPlotArea(55, 60, 520, 235, -1, -1, cd.Transparent, &Hcccccc, &Hcccccc)
Call c.setClipping()

' Add a title to the chart using dark grey (0x333333) 20pt Arial Bold font
Call c.addTitle("Real-Time Chart with Snapshot", "Arial Bold", 20, &H333333)

' Add a legend box at the top of the plot area using horizontal layout. Use 10pt Arial Bold font,
' transparent background and border, and line style legend icon.
Set b = c.addLegend(55, 30, False, "Arial Bold", 10)
Call b.setBackground(cd.Transparent, cd.Transparent)
Call b.setLineStyleKey()

' Set the x and y axis stems to transparent and the label font to 10pt Arial
Call c.xAxis().setColors(cd.Transparent)
Call c.yAxis().setColors(cd.Transparent)
Call c.xAxis().setLabelStyle("Arial", 10)
Call c.yAxis().setLabelStyle("Arial", 10)

' Add y-axis title using 12pt Arial font
Call c.yAxis().setTitle("Y-Axis Title Placeholder", "Arial", 12)

' For the automatic x and y axis labels, set the minimum spacing to 75 and 30 pixels.
Call c.xAxis().setTickDensity(75)
Call c.yAxis().setTickDensity(30)

' Set the x-axis label format
Call c.xAxis().setLabelFormat("{value|hh:nn:ss}")

' Create a line layer to plot the lines
Set layer = c.addLineLayer2()

' The x-coordinates are the timeStamps.
Call layer.setXData(timeStamps)

' The 3 data series are used to draw 3 lines. Here we put the latest data values as part of the data
' set name, so you can see them updated in the legend box.
Call layer.addDataSet(dataSeries1, &Hff0000, c.formatValue(dataSeries1(UBound(dataSeries1)), _
    "Alpha: {value|2}"))
Call layer.addDataSet(dataSeries2, &H00cc00, c.formatValue(dataSeries2(UBound(dataSeries2)), _
    "Beta: {value|2}"))
Call layer.addDataSet(dataSeries3, &H0000ff, c.formatValue(dataSeries3(UBound(dataSeries3)), _
    "Gamma: {value|2}"))

' Create the WebChartViewer to output the chart
Set viewer = cd.WebChartViewer(Request, "ChartImage1")

' Check if is download request
downloadFormat = Request("download")
If downloadFormat <> "" Then
    fname = c.formatValue(timeStamps(UBound(timeStamps)), "yyyymmddhhnnss")
    If downloadFormat = "pdf" Then
        ' Output in PDF and stream as attachment
        Call viewer.setChart(c, cd.PDF)
        Call viewer.streamChart(Response, "demo_" & fname & ".pdf")
        Call Response.End
    Else
        ' Output in PNG and stream as attachment
        Call viewer.setChart(c, cd.PNG)
        Call viewer.streamChart(Response, "demo_" & fname & ".png")
        Call Response.End
    End If
End If

' Check if is a stream request to update the chart
If viewer.IsStreamRequest Then
    ' Stream the updated chart to the browser
    Call viewer.setChart(c, cd.SVG)
    Call viewer.streamChart(Response)
    Call Response.End
End If

' Is the initial web page request. Output chart as usual.
Call viewer.setChart(c, cd.SVG)
%>

<!DOCTYPE html>
<html>
<head>
    <title>Real-Time Chart with Snapshot</title>
    <script type="text/javascript" src="cdjcv.js"></script>
</head>
<body style="margin:0px">
<table cellspacing="0" cellpadding="0" style="border:black 1px solid;">
    <tr>
        <td align="right" colspan="2" style="background:#000088; color:#ffff00; padding:0px 4px 2px 0px;">
            <a style="color:#FFFF00; font:italic bold 10pt Arial; text-decoration:none" href="http://www.advsofteng.com/">
                Advanced Software Engineering
            </a>
        </td>
    </tr>
    <tr valign="top">
        <td style="width:130px; background:#c0c0ff; border-right:black 1px solid; border-bottom:black 1px solid;">
            <br />
            <br />
            <div style="font:12px Verdana; padding:10px;">
                <b>Update Period</b><br />
                <select id="UpdatePeriod" style="width:110px">
                    <option value="5">5</option>
                    <option value="10" selected="selected">10</option>
                    <option value="20">20</option>
                    <option value="30">30</option>
                    <option value="60">60</option>
                </select>
                <br /><br /><br />
                <b>Time Remaining</b><br />
                <div style="width:108px; border:#888888 1px inset;">
                    <div style="margin:3px" id="TimeRemaining">0</div>
                </div>
            </div>
            <br />
            <br />
            <br />
            <br />
            <div style="text-align:center">
                <input type="button" value="Download PDF" style="width:112px; font:10pt Arial"
                    onclick="JsChartViewer.get('<%=viewer.Id%>').partialUpdateAsAttachment('download=pdf');" /><br/>
                <input type="button" value="Download PNG" style="width:112px; font:10pt Arial; margin-top:8px;"
                    onclick="JsChartViewer.get('<%=viewer.Id%>').partialUpdateAsAttachment('download=png');" />
            </div>
        </td>
        <td style="border-left:black 1px solid; padding:5px 0px 0px 5px;" >
            <!-- ****** Here is the chart image ****** -->
            <%=viewer.renderHTML()%>
        </td>
    </tr>
</table>
<script type="text/javascript">

//
// Executes once every second to update the countdown display. Updates the chart when the countdown reaches 0.
//
function timerTick()
{
    // Get the update period and the time left
    var updatePeriod = parseInt(document.getElementById("UpdatePeriod").value);
    var timeLeft = Math.min(parseInt(document.getElementById("TimeRemaining").innerHTML), updatePeriod) - 1;

    if (timeLeft == 0)
        // Can update the chart now
        JsChartViewer.get('<%=viewer.Id%>').streamUpdate();
    else if (timeLeft < 0)
        // Reset the update period
        timeLeft += updatePeriod;

    // Update the countdown display
    document.getElementById("TimeRemaining").innerHTML = timeLeft;
}
window.setInterval("timerTick()", 1000);

</script>
</body>
</html>