How to create an Excel chart with a trendline using C#, VB.NET?

Syncfusion Excel (XlsIO) library is a .NET Excel library used to create, read, and edit Excel documents. Also, converts Excel documents to PDF files.

This article explains how to create an Excel chart with a trendline using C# and VB.NET.

Include the following namespace in the Program.cs file.

C#

using Syncfusion.XlsIO;

VB.NET

Imports Syncfusion.XlsIO

Use the following code snippet for creating an Excel chart with a trendline.

C#

using (ExcelEngine excelEngine = new ExcelEngine())
{
    IApplication application = excelEngine.Excel;
    application.DefaultVersion = ExcelVersion.Xlsx;
    IWorkbook workbook = application.Workbooks.Open(Path.GetFullPath(@"Data/InputTemplate.xlsx"));
    IWorksheet sheet = workbook.Worksheets[0];

    //Create a chart
    IChartShape chart = sheet.Charts.Add();

    //Set chart type
    chart.ChartType = ExcelChartType.Column_Clustered;

    //Set data range in the worksheet
    chart.DataRange = sheet.Range["A1:B6"];
    chart.IsSeriesInRows = false;

    //Set chart title
    chart.ChartTitle = "Sales Details";

    //Set axis titles
    chart.PrimaryValueAxis.Title = "Amount(in $)";
    chart.PrimaryCategoryAxis.Title = "Items";

    //Set trendline for the chart series
    IChartSerie serie1 = chart.Series[0];
    serie1.TrendLines.Add(ExcelTrendLineType.Linear);
    serie1.TrendLines[0].Border.LinePattern = ExcelChartLinePattern.DashDot;
    serie1.TrendLines[0].Border.LineColor = Syncfusion.Drawing.Color.FromArgb(68, 114, 196);

    //Set legend
    chart.HasLegend = false;

    //Position the chart in the worksheet
    chart.TopRow = 8;
    chart.LeftColumn = 1;
    chart.BottomRow = 23;
    chart.RightColumn = 8;

    //Save the workbook
    workbook.SaveAs(Path.GetFullPath(@"Output/Output.xlsx"));
}

VB.NET

Using excelEngine As ExcelEngine = New ExcelEngine()
    Dim application As IApplication = excelEngine.Excel
    application.DefaultVersion = ExcelVersion.Xlsx
    Dim workbook As IWorkbook = application.Workbooks.Open("InputTemplate.xlsx")
    Dim sheet As IWorksheet = workbook.Worksheets(0)

    'Create a chart
    Dim chart As IChartShape = sheet.Charts.Add()

    'Set chart type
    chart.ChartType = ExcelChartType.Column_Clustered

    'Set data range in the worksheet
    chart.DataRange = sheet.Range("A1:B6")
    chart.IsSeriesInRows = False

    'Set chart title
    chart.ChartTitle = "Sales Details"

    'Set axis titles
    chart.PrimaryValueAxis.Title = "Amount(in $)"
    chart.PrimaryCategoryAxis.Title = "Items"

    'Set trendline for the chart series
    Dim serie1 As IChartSerie = chart.Series(0)
    serie1.TrendLines.Add(ExcelTrendLineType.Linear)
    serie1.TrendLines(0).Border.LinePattern = ExcelChartLinePattern.DashDot
    serie1.TrendLines(0).Border.LineColor = Color.FromArgb(68, 114, 196)

    'Set legend
    chart.HasLegend = False

    'Position the chart in the worksheet
    chart.TopRow = 8
    chart.LeftColumn = 1
    chart.BottomRow = 23
    chart.RightColumn = 8

    'Save the workbook
    workbook.SaveAs("Output.xlsx")
End Using

You can get the complete sample for creating an Excel chart with a trendline from

I hope you enjoyed learning about how to create an Excel chart with a trendline using C# and VB.NET in XlsIO.

You can refer to our XIsIO’s feature tour page to learn about its other groundbreaking features. Explore our UG documentation and online demos to understand how to manipulate data in Excel documents.

Take a moment to peruse the documentation where you can find basic Excel document processing options along with the features like import and export data, chart, formulas, conditional formatting, data validation, tables, pivot tables and, protect the Excel documents, and most importantly, the PDF, CSV and Image conversions with code examples.

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