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very new to C# and haven't worked with xml much so be gentle with me! I have a aspx page (C#) which draws chart data to a page and spits out an image (outputstream). At present the chart data is hard coded array(xy) just for dev purposes. What I want to achieve is to have the y values read from a txt or xml file. The x will always be hard coded and have a total of 21 in the index. However at any given time there may be <= 21 values for the Y value. I'll want the chart to stop plotting once it reaches a null value for Y. So in a nutshell I need to research/achieve reading xml values into a C# array and How to code.... for i = 1 to FirstInstanceOfNull in Y (so to speak) plot the chart Jay

jayp · Answer

thanks for that. I'll take a copy and digest it later today when I get time. Jay

j.mikejenkins · Answer

My first suggestion would not be to hard code anything. It would probably be better if you kept your chart dynamic. The example code below reads data points from an XML document and adds them to an ArrayList (.NET collection). The XML looks like the following: 0.0 0.0 5.0 10.0 10.0 15.0 15.0 20.0 20.0 25.0 The code below uses XPath expressions in conjunction with the XML framework provided by .NET XmlDocument l_doc = new XmlDocument(); l_doc.Load(@..\..\ChartPoints.xml); ArrayList l_listPoints = new ArrayList(); // select all Point Nodes that have ChartPoints as its parent node XmlNodeList l_listNodes = l_doc.SelectNodes(//ChartPoints/Point); for(int l_nIndex = 0; l_nIndex < l_listNodes.Count; l_nIndex++) { XmlNode l_currentNode = l_listNodes.Item(l_nIndex); // select the x and y node associated with the current node XmlNode l_NodeX = l_currentNode.SelectSingleNode(./XVal); XmlNode l_NodeY = l_currentNode.SelectSingleNode(./YVal); if(l_NodeX != null && l_NodeY != null) { CDataPoint l_Point = new CDataPoint(); l_Point.m_dX = Convert.ToDouble(l_NodeX.InnerText); l_Point.m_dY = Convert.ToDouble(l_NodeY.InnerText); l_listPoints.Add(l_Point); } }