How go I get the HTML for the chart image AREA map

Question

I am generating my chart dynamically using a separate file (httpHandler). Is there a way to get the HTML <area/> tag content that the image create when it is rendered im an ASPX page?

chart.RenderType = RenderType.ImageMap;
string result = chart.GetHtmlImageMap("trendmap");

The solution above returns a blank <map/> tag shown below:

<map name="trendmap">
    <area shape="rct" coords="0,0,0,0" alt=""/>
</map>

Is there any property I am missing?

Answer 1

To get Chart.GetHtmlImageMap result you have to render the chart first.
Call SaveImage(System.IO.Stream.Null) before Chart.GetHtmlImageMap.

Delian

Answer 2

Hi

I implemet this, but I cant' see the image

Protected

 

Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim chart1 As Chart = GetChart()
chart1.RenderType = RenderType.ImageMap
chart1.SaveImage(System.IO.Stream.Null)
Dim map As String = chart1.GetHtmlImageMap("trendmap")
End Sub

 

Function GetChart() As Chart
Dim Dates1 As Date = Today
Dim mySelectQuery As String = "SELECT Dates,Line,Loan FROM XCHART_200907 where Fecha >='" & Dates1 & "' order by Fecha"
Dim myConnection As New SqlConnection(myConnectionString)
Dim myReader As SqlDataReader
Dim myCommand As New SqlCommand(mySelectQuery, myConnection)

 

Dim adapter As New SqlDataAdapter(mySelectQuery, myConnection)
myConnection.Open()
Dim ax() As DateTime, ay1, ay2, unidades

 

ReDim ax(NumPuntos - 1)
ReDim ay1(NumPuntos - 1)
ReDim ay2(NumPuntos - 1)
myReader = myCommand.ExecuteReader()

 

While myReader.Readax(i) = myReader.GetValue(0)
ay1(i) = myReader.GetValue(1)
ay2(i) = myReader.GetValue(2)
i = i + 1
End While
myReader.Close()

 

Dim chart = New Chart()

chart.IsMapEnabled =

True
chart.Width = 600
chart.Height = 150
chart.Series.Add("one")
chart.Series.Add("two")

chart.Series(

"one").Points.DataBindXY(ax, ay1)
chart.Series("two").Points.DataBindXY(ax, ay2)

Return chart

 

End Function