Chart export in UpdatePanel

[Erik]

Hello.

I'm using a chart control in my application that is inside a UpdatePanel which is updated whenever the user change the date range field. Everything is working fine except when I use the server export function of the control. After the file is exported the controls in the page are unable to make a postback unless I reload the page. Here is my code:

<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">

        <ContentTemplate>

            <div class="row">

                <div class="col-md-7">

                    <ej:DateRangePicker ID="DateRangePicker1" runat="server" Width="200" Locale="pt-BR" AllowEdit="false" OnSelect="DateRangePicker1_Select"></ej:DateRangePicker>

                </div>

                <div class="col-md-5">

                    <asp:Button ID="Button1" runat="server" OnClientClick="download(this);" UseSubmitBehavior="false" />

                </div>

            </div>

            <ej:Chart ID="Chart1" runat="server" Height="400" Locale="pt-BR" IsResponsive="true" OnServerExporting="ExportChart" ClientIDMode="Static" EnableCanvasRendering="true">

                <PrimaryXAxis Title-Text="Month" LabelFormat="MMM/yyyy" LabelIntersectAction="Rotate45" />

                <PrimaryYAxis Title-Text="Total" />

                <CommonSeriesOptions EnableAnimation="True" Tooltip-Visible="true" Tooltip-Format="#point.x# : #point.y# #series.name#">

                    <Marker>

                        <DataLabel Visible="True" ShowEdgeLabels="true" EnableContrastColor="true">

                        </DataLabel>

                    </Marker>

                </CommonSeriesOptions>

                <Series>

                    <ej:Series Name="Series1" XName="Xvalue" YName="YValue1"></ej:Series>

                    <ej:Series Name="Series2" XName="Xvalue" YName="YValue2"></ej:Series>

                </Series>

                <Legend Position="Top"></Legend>

            </ej:Chart>

        </ContentTemplate>

        <Triggers>

            <asp:AsyncPostBackTrigger ControlID="DateRangePicker1" EventName="Select" />

        </Triggers>

    </asp:UpdatePanel>

I tried using the PostBackTrigger for the export button with no success. Is there a example on how to export the chart inside a UpdatePanel? I'm using the EJ1 by the way.

Thanks in advance. Regards. 

[Durga Gopalakrishnan]

Hi Erik, 

We have analysed your query. We were able to export the chart rendered inside UpdatePanel. We have attached sample for your reference. Please check with it. We are unable to reproduce the reported issue at our end. Kindly provide an issue reproduced sample or try to reproduce an issue in attached sample to proceed further. 

Code Snippet 

ChartFeatures.aspx 

<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server"> 

    <asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional"> 

    <ContentTemplate> 

        <ej:Chart ID="Chart1" OnServerExporting="ExportChart"> 

            <ExportSettings Mode="Server" /> 

        </ej:Chart> 

    </ContentTemplate> 

    </asp:UpdatePanel> 

<script type="text/javascript"> 

     function download() { 

          $("#Chart1").ejChart("export"); 

     } 

</script> 

</asp:Content> 

 

ChartFeatures.aspx.cs 

protected void ExportChart(object sender, Syncfusion.JavaScript.Web.ChartEventArgs e) 

  { 

     string Format = "png"; 

     string FileName = "Chart"; 

     string DataURL = e.Arguments["Data"].ToString(); 

     DataURL = DataURL.Remove(0, DataURL.IndexOf(',') + 1); 

     MemoryStream stream = new MemoryStream(Convert.FromBase64String(DataURL)); 

     stream.WriteTo(Response.OutputStream); 

     Response.ContentType = "application/octet-stream"; 

     Response.AddHeader("Content-Disposition", String.Format("attachment;filename={0}", FileName + "." + Format)); 

     Response.Flush(); 

     stream.Close(); 

     stream.Dispose(); 

  } 

Screenshot 

 

Sample 

https://www.syncfusion.com/downloads/support/directtrac/general/ze/ChartUpdatePanel-392791468.zip 

Please revert us, if you have any concerns. 

Regards, 

Durga G

[Erik]

Hi Durga.

I think I found the problem but I don't know how to solve... Every time I export the chart the application does two postback: one from the chart control and the other from the button. Here is my Page_Load function:

        protected void Page_Load(object sender, EventArgs e)

        {

            if (!IsPostBack)

            {

                List<ColumnChartData> data = new List<ColumnChartData>();

                data.Add(new ColumnChartData("USA", 50, 70, 45));

                data.Add(new ColumnChartData("China", 40, 60, 55));

                data.Add(new ColumnChartData("Japan", 70, 60, 50));

                data.Add(new ColumnChartData("Australia", 60, 56, 40));

                data.Add(new ColumnChartData("France", 50, 45, 35));

                data.Add(new ColumnChartData("Germany", 40, 30, 22));

                data.Add(new ColumnChartData("Italy", 40, 35, 37));

                data.Add(new ColumnChartData("Sweden", 30, 25, 27));

                //Binding Datasource to Chart

                this.Chart1.DataSource = data;

                this.Chart1.DataBind();

            }

        }

I check if it is not a postback to prevent reloading the chart with the initial values (as it can be filtered by the RangeDatePicker control).But this render the chart empty on the page every time I export.

So, should I reload the chart with the current value from the RangeDatePicker on every postback or there is a way to send the postback for export but without having to reload the chart control?

Thanks for the support. Regards.

[Durga Gopalakrishnan]

Hi Erik, 

We have analysed your query. We suggest you to bind the data to series instead of chart, to overcome an empty chart rendering on clicking export button. We have prepared sample based on your requirement. Please check with the below code snippet and sample. 

Code Snippet 

 

ChartFeatures.aspx 

<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server"> 

    <asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional"> 

        <ContentTemplate> 

           <ej:Chart ID="Chart1" runat="server" OnServerExporting="ExportChart"> 

           </ej:Chart> 

        </ContentTemplate> 

    </asp:UpdatePanel> 

</asp:Content> 

 

ChartFeatures.aspx.cs 

protected void Page_Load(object sender, EventArgs e) 

{ 

    if (!IsPostBack) 

    { 

        this.bindChartData(); 

   } 

} 

private void bindChartData() 

{ 

    //Binding Datasource to Chart Series 

    for (int j = 0; j < this.Chart1.Series.Count; j++) 

    { 

       this.Chart1.Series[j].DataSource = data; 

    } 

    this.Chart1.DataBind(); 

} 

 

Screenshot 

 

 

 

Sample 

https://www.syncfusion.com/downloads/support/directtrac/general/ze/PostBack1328838011.zip 

 

Kindly revert us, if you have any concerns. 

 

Regards, 

Durga G 

[plein]

Hi Durga.

I think I found the problem but I don't know how to solve... Every time I export the chart the application does two postback: one from the chart control and the other from the button. Here is my Page_Load function:

        protected void Page_Load(object sender, EventArgs e)

        {

            if (!IsPostBack)

            {

                List data = new List();

                data.Add(new ColumnChartData("USA", 50, 70, 45));

                data.Add(new ColumnChartData("China", 40, 60, 55));

                data.Add(new ColumnChartData("Japan", 70, 60, 50));

                data.Add(new ColumnChartData("Australia", 60, 56, 40));

                data.Add(new ColumnChartData("France", 50, 45, 35));

                data.Add(new ColumnChartData("Germany", 40, 30, 22));

                data.Add(new ColumnChartData("Italy", 40, 35, 37));

                data.Add(new ColumnChartData("Sweden", 30, 25, 27));

                //Binding Datasource to Chart

                this.Chart1.DataSource = data;

                this.Chart1.DataBind();

            }

        }

I check if it is not a postback to prevent reloading the chart with the initial values (as it can be filtered by the RangeDatePicker control).But this render the chart empty on the page every time I export.

So, should I reload the chart with the current liteblue value from the RangeDatePicker on every postback or there is a way to send the postback for export but without having to reload the chart control?

Thanks for the support. Regards.

Support is awesome and I love this.

[Srihari Muthukaruppan]

Hi Plein,  

Most welcome. Kindly get in touch with us, if you requires further assistance. We are always happy in assisting you.   

   

Thanks,   

Srihari M 

[Erik]

Hi Durga.

I've made the changes and it worked. Thank you very much for the help.

Regards,

[Srihari Muthukaruppan]

Hi Erik,   

 

Most welcome. Kindly get in touch with us, if you requires further assistance. We are always happy in assisting you.    

    

Thanks,    

Srihari M