Cumulative Graph in ASP??

[phil1995]

I am attempting to create an ASP application that uses a cumulative graph. The problem I have is that every time a control button is activated, the page reloads and the previous data dissapears. This was not an issue in windows froms. How can I retain the current series on page reload when adding another series?

I assume this is something to do with the TEMPCHART setting. Can someone tell me how to set this to Session? I am new to ASP and the tutorial in section 9 did not make it clear to me.

[Christopher]

Hi -

You can use code similar to the following:

Code: Select all

	private void Page_Load(object sender, System.EventArgs e)
		{
			// ****************************************************
			//The data load code for WebChart1 demostrates a technique to save 
			//data between page calls. The Chart is saved as a TeeChart template 
			//to a session variable.
			// ****************************************************
			Steema.TeeChart.Chart ch1=WebChart1.Chart;
			MemoryStream tmpChart=new MemoryStream();

			if (Session["ch1"]==null)
			{			
				//setup Chart
				if (ch1.Series.Count<2)
				{ 
					ch1.Series.Add(new Steema.TeeChart.Styles.Points());
					ch1.Series.Add(new Steema.TeeChart.Styles.Points());
				}
				ch1.Header.Text="Chart 1.";

				((Steema.TeeChart.Styles.Points)ch1.Series[0]).Pointer.Pen.Visible=false;
				((Steema.TeeChart.Styles.Points)ch1.Series[1]).Pointer.Pen.Color=Color.FromArgb(79,79,255);
		
				ch1.Series[0].Color=Color.FromArgb(255,199,26);
				ch1.Series[1].Color=Color.FromArgb(106,106,255);

				ch1.Series[0].FillSampleValues(5);
				ch1.Series[1].FillSampleValues(5);
				//export Chart to a MemoryStream template
				ch1.Export.Template.Save(tmpChart);
				//save template to a Session variable
				Session.Add("ch1",tmpChart);
			}
			else
			{
				//retrieve the session stored Chart
				tmpChart=(MemoryStream)Session["ch1"];
				//set the Stream position to 0 as the last read/write
				//will have moved the position to the end of the stream
				tmpChart.Position=0;
				//import saved Chart
				ch1.Import.Template.Load(tmpChart);
			}
		
		}