How to convert the chart created from external data range using XlsIO?

2 mins read

This article explains how to convert chart created with external data range using XlsIO in C#/VB.NET.

What is chart with external data?

The chart created with the data from an external workbook is called chart with external data. The chart from the current worksheet holds a chart cache to maintain the chart data. For conversion, ExcelChartToImageConverter uses that cache information when the chart is created with external data range. By default, XlsIO does not parse the chart cache information. So, we must set the IsChartCacheEnabled property to true in IApplication to parse that cache information before opening the excel file. After parsing the cache information, it is used for converting the chart properly.

To convert chart created with external data range, you need to follow the below steps.

Steps to convert chart with external data range

Enable the chart cache parsing to parse the data from the chart.

//Enable the chart cache parsing
application.IsChartCacheEnabled = true;

Instantiate ChartToImageConverter in IApplication and set the scaling mode for the chart while conversion.

//Instantiate chart to image converter
application.ChartToImageConverter = new ChartToImageConverter();
application.ChartToImageConverter.ScalingMode = ScalingMode.Best;

Convert the workbook to PDF and saving the pdf file.

//Open the Excel Document to Convert
ExcelToPdfConverter converter = new ExcelToPdfConverter(workbook);
 
//Converting workbook to PDF
PdfDocument doc = converter.Convert();
 
//Saving the PDF document
Stream stream = File.Create("Output.pdf");
doc.Save(stream);

To know more about chart conversion using XlsIO, please refer the documentation.

Download input file

Download Complete sample

The following C#/VB.NET complete code snippet shows how to convert chart with external data range.

using Syncfusion.ExcelChartToImageConverter;
using Syncfusion.ExcelToPdfConverter;
using Syncfusion.Pdf;
using Syncfusion.XlsIO;
using System.IO;
using System.Reflection;
 
namespace XlsIO_Sample
{
    class Program
    {
        static void Main(string[] args)
        {
            using (ExcelEngine excelEngine = new ExcelEngine())
            {
                IApplication application = excelEngine.Excel;
 
                //Enable the chart cache parsing
                application.IsChartCacheEnabled = true;
 
                //Instantiate chart to image converter
                application.ChartToImageConverter = new ChartToImageConverter();
                application.ChartToImageConverter.ScalingMode = ScalingMode.Best;
 
                IWorkbook workbook;
 
                //Open existing workbook with data entered
                Assembly assembly = typeof(Program).GetTypeInfo().Assembly;
                Stream fileStream = assembly.GetManifestResourceStream("CSharpSample.Sample.xlsx");
 
                workbook = application.Workbooks.Open(fileStream, ExcelOpenType.Automatic);
 
                IChart chart = workbook.Worksheets[0].Charts[0];
 
                IRange range = chart.DataRange;
 
                //Open the Excel Document to Convert
                ExcelToPdfConverter converter = new ExcelToPdfConverter(workbook);
 
                //Converting workbook to PDF
                PdfDocument doc = converter.Convert();
 
                //Saving the PDF document
                Stream stream = File.Create("Output.pdf");
                doc.Save(stream);
 
                converter.Dispose();
                doc.Close(true);
            }
        }
    }
}

Imports Syncfusion.XlsIO
Imports Syncfusion.ExcelChartToImageConverter
Imports Syncfusion.ExcelToPdfConverter
Imports Syncfusion.Pdf
Imports System.Reflection
Imports System.IO
 
Namespace XlsIO_Sample
    Module Program
 
        Public Sub Main()
            'Instantiate the spreadsheet creation engine
            Using excelEngine As ExcelEngine = New ExcelEngine()
 
                Dim application As IApplication = excelEngine.Excel
 
                'Enable the chart cache parsing
                application.IsChartCacheEnabled = False
 
                'Instantiate chart to image converter
                application.ChartToImageConverter = New ChartToImageConverter()
                application.ChartToImageConverter.ScalingMode = ScalingMode.Best
 
                'Open existing workbook 
                Dim workbook As IWorkbook
                Dim assembly As Assembly = GetType(Program).GetTypeInfo().Assembly
                Dim fileStream As Stream = assembly.GetManifestResourceStream("VBSample.Sample.xlsx")
                workbook = application.Workbooks.Open(fileStream, ExcelOpenType.Automatic)
 
                'Open the Excel Document to Convert
                Dim converter As New ExcelToPdfConverter(workbook)
 
                'Converting to PDF
                Dim doc As PdfDocument = converter.Convert()
 
                'Saving the pdf file
                Dim stream As Stream = File.Create("Output.pdf")
                doc.Save(stream)
 
                converter.Dispose()
                excelEngine.Dispose()
                doc.Close(True)
            End Using
        End Sub
    End Module
 
End Namespace

The below screenshot shows the output chart with external data range after conversion.