## Combining FusionCharts, ASP.NET & JavaScript (dataXML) method
In our previous example, we had combined FusionCharts, ASP.NET and JavaScript to create client side dynamic charts. We were updating the chart by asking it to fetch new data from server and update itself, without incurring any page refreshes. In this example, instead of asking the chart to get XML data from server, we'll provide updated XML data to chart using JavaScript functions. The chart will simply accept that XML data and render. This method can effectively be used in your AJAX applications, where your JavaScript code gets the updated XML from server and then provides it to charts locally. You can process the data received from AJAX Calls, build XML from it and finally provide it to the chart. Before you proceed with the contents in this page, we strictly recommend you to please go through the sections "How FusionCharts works?" and "Basic Examples", as we'll directly use a lot of concepts defined in those sections. The code discussed in this example is present in Download Package > Code > VB_NET > DB_JS folder.
Defining the applicaton
We'll carry on from our previous example and convert it to use JavaScript + XML, so that the new XML is provided to the chart using JavaScript functions - the charts NO more directly request data from server. To attain this, we send all the pertinent data from our server to the end viewer as JavaScript arrays in the same page. The JavaScript arrays are dynamically generated by ASP.NET pages at run-time and filled with data. Effectively, we will do the following: Contain both the pie chart (summary) and column chart (detailed) in one page (Default.aspx). When the page loads, the pie chart would use dataXML method to show summary of all factories. This data will be built in Default.aspx itself. There will be a JavaScript array named as data in this page. This array will contain detailed data for the factories. The array will be dynamically built using ASP.NET and then outputted as JavaScript code. Apart from the data in JavaScript, we'll also have a local JavaScript function updateChart(), which would process the data in this array and convert it to XML data document, for direct usage by the column chart. The column chart would initialize with no data, as the user has not selected a factory initially. We'll customize the "No data to display" message of the chart to show a friendly message. The pie chart would have JavaScript links defined for each pie slice. This JavaScript links refer to updateChart() JavaScript function present on the same page. We'll later see how to hand code this function. When a pie is clicked, the factory ID is passed to this function. The updateChart() function is responsible for udapting the column chart. It generates the XML data from data stored in JavaScript data array and conveys it to the column chart. The column chart would now accept this XML data, parse it and finally render.
Creating the page - Default.aspx
Both the charts and JavaScript functions to manipulate the charts is contained in Default.aspx. It has the following code:
<%@ Page language="c#" Codebehind="Default.aspx.vb" AutoEventWireup="false" Inherits="InfoSoftGlobal.GeneralPages.ASP.NET.DB_JS._Default" %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" > <HTML> <HEAD> <TITLE>FusionCharts - Database + JavaScript Example </TITLE> <SCRIPT LANGUAGE="Javascript" SRC="../../FusionCharts/FusionCharts.js"> </SCRIPT> <SCRIPT LANGUAGE="JavaScript"> //Here, we use a mix of server side script (VB.NET) and JavaScript to //render our data for factory chart in JavaScript variables. We'll later //utilize this data to dynamically plot charts. //All our data is stored in the data array. From VB.NET, we iterate through //each recordset of data and then store it as nested arrays in this data array. var data = new Array(); //Write the data as JavaScript variables here <%=GetScript()%> //The data is now present as arrays in JavaScript. Local JavaScript functions //can access it and make use of it. We'll see how to make use of it. /** * updateChart method is invoked when the user clicks on a pie slice. * In this method, we get the index of the factory, build the XML data * for that that factory, using data stored in data array, and finally * update the Column Chart. * @param factoryIndex Sequential Index of the factory. */ function updateChart(factoryIndex){ //Storage for XML data document var strXML = "<chart palette='2' caption='Factory " + factoryIndex + " Output ' subcaption='(In Units)' xAxisName='Date' showValues='1' labelStep='2' >"; //Add <set> elements var i=0; for (i=0; i<data[factoryIndex].length; i++){ strXML = strXML + "<set label='" + data[factoryIndex][i][0] + "' value='" + data[factoryIndex][i][1] + "' />"; } //Closing Chart Element strXML = strXML + "</chart>"; //Get reference to chart object using Dom ID "FactoryDetailed" var chartObj = getChartFromId("FactoryDetailed"); //Update it's XML chartObj.setDataXML(strXML); } </SCRIPT> </HEAD> <body> <%=GetFactorySummayChartHtml()%> <BR> <%=GetFactoryDetailedChartHtml()%> <form id='form1' name='form1' method='post' runat="server"> <!-- Note that the chart is outside FORM element, as it will interact with JS --> </form> </body> </HTML> Code in code behind page: ''' ''' The following string will contain the JS Data and variables. ''' This string will be built in ASP.NET and rendered at run-time as JavaScript. ''' Public jsVarString As String = String.Empty Public Function GetFactorySummayChartHtml() As String 'In this example, we show a combination of database + JavaScript rendering using FusionCharts. 'The entire app (page) can be summarized as under. This app shows the break-down 'of factory wise output generated. In a pie chart, we first show the sum of quantity 'generated by each factory. These pie slices, when clicked would show detailed date-wise 'output of that factory. 'The XML data for the pie chart is fully created in ASP.NET at run-time. ASP.NET interacts 'with the database and creates the XML for this. 'Now, for the column chart (date-wise output report), we do not submit request to the server. 'Instead we store the data for the factories in JavaScript arrays. These JavaScript 'arrays are rendered by our ASP.NET Code (at run-time). We also have a few defined JavaScript 'functions which react to the click event of pie slice. 'We've used an Access database which is present in ../DB/FactoryDB.mdb. 'It just contains two tables, which are linked to each other. 'Before the page is rendered, we need to connect to the database and get the 'data, as we'll need to convert this data into JavaScript variables. 'Database Objects Dim factoryQuery As String = "select * from Factory_Master" Dim indexCount As Integer 'Initialize the Pie chart with sum of production for each of the factories 'xmlData will be used to store the entire XML document generated Dim xmlData As String Dim connection As OdbcConnection = DbHelper.Connection(DbHelper.ConnectionStringFactory) Dim factoryCommand As OdbcCommand = New OdbcCommand(factoryQuery, connection) Dim factoryAdapter As OdbcDataAdapter = New OdbcDataAdapter(factoryCommand) Dim factoryTable As DataTable = New DataTable factoryAdapter.Fill(factoryTable) 'Initialize Index indexCount = 0 'Generate the chart element xmlData = "<chart caption='Factory Output report' subCaption='By Quantity' pieSliceDepth='30' showBorder='1' formatNumberScale='0' numberSuffix=' Units' >" For Each row As DataRow In factoryTable.Rows indexCount = (indexCount + 1) Dim quantityQuery As String = ("select sum(Quantity) as TotOutput from Factory_Output where FactoryId=" + row("FactoryId").ToString()) Dim quantityCommand As OdbcCommand = New OdbcCommand(quantityQuery, connection) 'Build XML Data for pie chart xmlData = (xmlData + ("<set label='" _ + (row("FactoryName") + ("' value='" _ + (quantityCommand.ExecuteScalar.ToString + ("' link='javaScript:updateChart(" _ + (indexCount.ToString + ")'/>"))))))) Next connection.Close() xmlData = (xmlData + "</chart>") Dim chartBuilder As System.Text.StringBuilder = New System.Text.StringBuilder 'Create the chart - Pie 3D Chart with data from xmlData Return FusionCharts.RenderChart("../../FusionCharts/Pie3D.swf", "", xmlData, "FactorySum", "500", "250", False, True) End Function Public Function GetFactoryDetailedChartHtml() As String Return FusionCharts.RenderChart("../../FusionCharts/Column2D.swf?ChartNoDataText=Please select a factory from pie chart above to view " & _ "detailed data.", "", "<chart></chart>", "FactoryDetailed", "600", "250", False, True) End Function Public Function GetScript() As String 'Iterate through each factory Dim factoryQuery As String = "select * from Factory_Master" Dim indexCount As Integer = 0 Dim factoryTable As DataTable = New DataTable Dim connection As OdbcConnection = FusionCharts.Connection(FusionCharts.ConnectionStringFactory) Dim factoryCommand As OdbcCommand = New OdbcCommand(factoryQuery, connection) Dim factoryAdapter As OdbcDataAdapter = New OdbcDataAdapter(factoryCommand) factoryAdapter.Fill(factoryTable) For Each row As DataRow In factoryTable.Rows indexCount = (indexCount + 1) 'Build JavaScript array code as string jsVarString = (jsVarString + ("" & vbTab & vbTab & " data[" _ + (indexCount.ToString + ("] = new Array();" + Environment.NewLine)))) Dim outputQuery As String = ("select * from Factory_Output where FactoryId=" _ + (row("FactoryId").ToString + " order by DatePro Asc")) Dim outputCommand As OdbcCommand = New OdbcCommand(outputQuery, connection) Dim outputAdapter As OdbcDataAdapter = New OdbcDataAdapter(outputCommand) Dim outputTable As DataTable = New DataTable outputAdapter.Fill(outputTable) For Each outputRow As DataRow In outputTable.Rows jsVarString = (jsVarString + ("" & vbTab & vbTab & " data[" _ + (indexCount.ToString + ("].push(new Array('" _ + (CType(outputRow("DatePro"), DateTime).Day.ToString + ("/" _ + (CType(outputRow("DatePro"), DateTime).Month.ToString + ("'," _ + (outputRow("Quantity").ToString + ("));" + Environment.NewLine)))))))))) Next Next Return jsVarString End Function
In this page, before rendering any HTML code, we first generate all the data in database as JavaScript array. To do so, we use string concatenation in ASP.NET variables to store all data as JavaScript array code. Once the JavaScript code is built in our ASP.NET variable, we write it out in the <SCRIPT> section of HTML <HEAD>. <SCRIPT LANGUAGE="JavaScript"> var data = new Array(); <% <%=GetScript()%> %> </SCRIPT> If you run this page and view the source JavaScript code, you'll see the following:
var data = new Array(); data[1] = new Array(); data[1].push(new Array('1/1',21)); data[1].push(new Array('2/1',23)); data[1].push(new Array('3/1',22)); data[1].push(new Array('4/1',24)); data[1].push(new Array('5/1',32)); data[1].push(new Array('6/1',21)); data[1].push(new Array('7/1',34)); data[1].push(new Array('8/1',32)); data[1].push(new Array('9/1',32)); data[1].push(new Array('10/1',23)); data[1].push(new Array('11/1',23)); data[1].push(new Array('12/1',32)); data[1].push(new Array('13/1',53)); data[1].push(new Array('14/1',23)); data[1].push(new Array('15/1',26)); data[1].push(new Array('16/1',43)); data[1].push(new Array('17/1',16)); data[1].push(new Array('18/1',45)); data[1].push(new Array('19/1',65)); data[1].push(new Array('20/1',54)); data[2] = new Array(); data[2].push(new Array('1/1',121)); data[2].push(new Array('2/1',123)); data[2].push(new Array('3/1',122)); data[2].push(new Array('4/1',124)); data[2].push(new Array('5/1',132)); data[2].push(new Array('6/1',121)); data[2].push(new Array('7/1',134)); data[2].push(new Array('8/1',132)); data[2].push(new Array('9/1',132)); data[2].push(new Array('10/1',123)); data[2].push(new Array('11/1',123)); data[2].push(new Array('12/1',132)); data[2].push(new Array('13/1',153)); data[2].push(new Array('14/1',123)); data[2].push(new Array('15/1',126)); data[2].push(new Array('16/1',143)); data[2].push(new Array('17/1',116)); data[2].push(new Array('18/1',145)); data[2].push(new Array('19/1',165)); data[2].push(new Array('20/1',154)); data[3] = new Array(); data[3].push(new Array('1/1',54)); data[3].push(new Array('2/1',56)); data[3].push(new Array('3/1',89)); data[3].push(new Array('4/1',56)); data[3].push(new Array('5/1',98)); data[3].push(new Array('6/1',76)); data[3].push(new Array('7/1',65)); data[3].push(new Array('8/1',45)); data[3].push(new Array('9/1',75)); data[3].push(new Array('10/1',54)); data[3].push(new Array('11/1',75)); data[3].push(new Array('12/1',76)); data[3].push(new Array('13/1',34)); data[3].push(new Array('14/1',97)); data[3].push(new Array('15/1',55)); data[3].push(new Array('16/1',43)); data[3].push(new Array('17/1',16)); data[3].push(new Array('18/1',35)); data[3].push(new Array('19/1',78)); data[3].push(new Array('20/1',75));
You can clearly see that our ASP.NET code has outputted JavaScript code that can now locally create an array and feed it with requisite data. Now, before we get to the JavaScript functions, let's first see what we're doing in our ASP.NET Code. We first create the XML data document for Pie chart - summary of factory output. For each <set>, we provide a JavaScript link to the updateChart() function and pass the factory ID to it as shown in the line below: xmlData = (xmlData + ("<set label='" _ + (row("FactoryName") + ("' value='" _ + (quantityCommand.ExecuteScalar.ToString + ("' link='javaScript:updateChart(" _ + (indexCount.ToString + ")'/>"))))))) We now render the Pie 3D chart using dataXML method. The Pie 3D chart has its DOM Id as FactorySum: FusionCharts.RenderChart("../../FusionCharts/Pie3D.swf", "", xmlData, "FactorySum", 500, 250, false, false) Now, we render an empty Column 2D chart with <chart></chart> data initially. We also change the "No data to display." error to a friendly and intuitive "Please select a factory from pie chart above to view detailed data." This chart has its DOM Id as FactoryDetailed. FusionCharts.RenderChart("../../FusionCharts/Column2D.swf?ChartNoDataText=Please select a factory from pie chart above to view detailed data.", "", "<chart></chart>", "FactoryDetailed", 600, 250, false, false) Effectively, our page is now set to show two charts. The pie chart shows the summary data provided to it using dataXML method. The column chart shows the above "friendly" error message. Now, when each pie slice is clicked, the updateChart() JavaScript function is called and the factoryID of the pie is passed to it. This function is responsible for updating the column chart and contains the following code:
function updateChart(factoryIndex){ //Storage for XML data document var strXML = "<chart palette='2' caption='Factory " + factoryIndex + " Output ' subcaption='(In Units)' xAxisName='Date' showValues='1' labelStep='2' >"; //Add <set> elements var i=0; for (i=0; i<data[factoryIndex].length; i++){ strXML = strXML + "<set label='" + data[factoryIndex][i][0] + "' value='" + data[factoryIndex][i][1] + "' />"; } //Closing Chart Element strXML = strXML + "</chart>"; //Get reference to chart object using Dom ID "FactoryDetailed" var chartObj = getChartFromId("FactoryDetailed"); //Update it's XML chartObj.setDataXML(strXML); }
Here, We first create the XML data document for the column chart by iterating through data contained in our JavaScript data array. Thereafter, we convery this XML data to the column chart. To do so, we first get a reference to the column chart using it's DOM Id FactoryDetailed. We use the getChartFromId() function defined in FusionCharts.js to do so. Once we've the reference to the chart, we simply call the setDataXML method of the chart and pass it the XML data document. This updates the chart with new data. If you've your chart objects inside <FORM> elements, you CANNOT use getChartFromId() method to get a reference to the chart, as the DOM Hierarchy of the chart object has changed. You'll get a JavaScript "<<ChartId>> is undefined" error. In these cases, you'll manually need to get a reference to the chart object. Or, you can opt to place the chart object outside <FORM> element. When you now see the application, the initial state would look as under:
And when you click on a pie slice, the following would appear on the same page (without involving any browser refreshes):
This example demonstrated a very basic sample of the integration capabilities possible with FusionCharts v3. For advanced demos, you can see and download our FusionCharts Blueprint/Demo Applications.