private void btnExcelToPdf_Click(object sender, EventArgs e)
{
    // Create an Excel to PDF converter object with default settings
    ExcelToPdfConverter excelToPdfConverter = new ExcelToPdfConverter();

    // Set license key received after purchase to use the converter in licensed mode
    // Leave it not set to use the converter in demo mode
    excelToPdfConverter.LicenseKey = "4218bHp9bHxsemJ8bH99Yn1+YnV1dXVsfA==";

    // PDF Page Options

    // Set PDF page size which can be a predefined size like A4 or a custom size in points 
    // Leave it not set to have a default A4 PDF page
    excelToPdfConverter.PdfDocumentOptions.PdfPageSize = SelectedPdfPageSize();

    // Set PDF page orientation to Portrait or Landscape
    // Leave it not set to have a default Portrait orientation for PDF page
    excelToPdfConverter.PdfDocumentOptions.PdfPageOrientation = SelectedPdfPageOrientation();

    // Set PDF page margins in points or leave them not set to have a PDF page without margins
    excelToPdfConverter.PdfDocumentOptions.LeftMargin = float.Parse(leftMarginTextBox.Text);
    excelToPdfConverter.PdfDocumentOptions.RightMargin = float.Parse(rightMarginTextBox.Text);
    excelToPdfConverter.PdfDocumentOptions.TopMargin = float.Parse(topMarginTextBox.Text);
    excelToPdfConverter.PdfDocumentOptions.BottomMargin = float.Parse(bottomMarginTextBox.Text);

    // Excel Content Destination and Spacing Options

    // Set Excel content destination in PDF page
    if (xLocationTextBox.Text.Length > 0)
        excelToPdfConverter.PdfDocumentOptions.X = float.Parse(xLocationTextBox.Text);
    if (yLocationTextBox.Text.Length > 0)
        excelToPdfConverter.PdfDocumentOptions.Y = float.Parse(yLocationTextBox.Text);
    if (contentWidthTextBox.Text.Length > 0)
        excelToPdfConverter.PdfDocumentOptions.Width = float.Parse(contentWidthTextBox.Text);
    if (contentHeightTextBox.Text.Length > 0)
        excelToPdfConverter.PdfDocumentOptions.Height = float.Parse(contentHeightTextBox.Text);

    // Set Excel content top and bottom spacing or leave them not set to have no spacing for the Excel content
    excelToPdfConverter.PdfDocumentOptions.TopSpacing = float.Parse(topSpacingTextBox.Text);
    excelToPdfConverter.PdfDocumentOptions.BottomSpacing = float.Parse(bottomSpacingTextBox.Text);

    // Scaling Options

    // Use this option to fit the Excel content width in PDF page width
    // By default this property is true and the Excel content can be resized to fit the PDF page width
    excelToPdfConverter.PdfDocumentOptions.FitWidth = fitWidthCheckBox.Checked;

    // Use this option to enable the Excel content stretching when its width is smaller than PDF page width
    // This property has effect only when FitWidth option is true
    // By default this property is false and the Excel content is not stretched
    excelToPdfConverter.PdfDocumentOptions.StretchToFit = stretchCheckBox.Checked;

    // Use this option to automatically dimension the PDF page to display the Excel content unscaled
    // This property has effect only when the FitWidth property is false
    // By default this property is true and the PDF page is automatically dimensioned when FitWidth is false
    excelToPdfConverter.PdfDocumentOptions.AutoSizePdfPage = autoSizeCheckBox.Checked;

    // Use this option to fit the Excel content height in PDF page height
    // If both FitWidth and FitHeight are true then the Excel content will resized if necessary to fit both width and height 
    // preserving the aspect ratio at the same time
    // By default this property is false and the Excel content is not resized to fit the PDF page height
    excelToPdfConverter.PdfDocumentOptions.FitHeight = fitHeightCheckBox.Checked;

    // Use this option to render the whole Excel content into a single PDF page
    // The PDF page size is limited to 14400 points
    // By default this property is false
    excelToPdfConverter.PdfDocumentOptions.SinglePage = singlePageCheckBox.Checked;

    // Add Header

    // Enable header in the generated PDF document
    excelToPdfConverter.PdfDocumentOptions.ShowHeader = addHeaderCheckBox.Checked;

    // Draw header elements
    if (excelToPdfConverter.PdfDocumentOptions.ShowHeader)
        DrawHeader(excelToPdfConverter, true);

    // Add Footer

    // Enable footer in the generated PDF document
    excelToPdfConverter.PdfDocumentOptions.ShowFooter = addFooterCheckBox.Checked;

    // Draw footer elements
    if (excelToPdfConverter.PdfDocumentOptions.ShowFooter)
        DrawFooter(excelToPdfConverter, true, true);

    Cursor = Cursors.WaitCursor;

    string outPdfFile = @"DemoAppFiles\Output\ExcelToPdf.pdf";
    try
    {
        string excelFile = excelFilePathTextBox.Text;

        // Convert the Excel document to a PDF document
        byte[] outPdfBuffer = excelToPdfConverter.ConvertExcelFile(excelFile);

        // Write the memory buffer in a PDF file
        System.IO.File.WriteAllBytes(outPdfFile, outPdfBuffer);
    }
    catch (Exception ex)
    {
        // The Excel to PDF conversion failed
        MessageBox.Show(String.Format("Excel to PDF Error. {0}", ex.Message));
        return;
    }
    finally
    {
        Cursor = Cursors.Arrow;
    }

    // Open the created PDF document in default PDF viewer
    try
    {
        System.Diagnostics.Process.Start(outPdfFile);
    }
    catch (Exception ex)
    {
        MessageBox.Show(String.Format("Cannot open created PDF file '{0}'. {1}", outPdfFile, ex.Message));
    }
}

/// <summary>
/// Draw the header elements
/// </summary>
/// <param name="excelToPdfConverter">The Excel to PDF Converter object</param>
/// <param name="drawHeaderLine">A flag indicating if a line should be drawn at the bottom of the header</param>
private void DrawHeader(ExcelToPdfConverter excelToPdfConverter, bool drawHeaderLine)
{
    string headerImagePath = System.IO.Path.Combine(Application.StartupPath,
                @"DemoAppFiles\Input\Images\logo.jpg");

    // Set the header height in points
    excelToPdfConverter.PdfHeaderOptions.HeaderHeight = 60;

    // Set header background color
    excelToPdfConverter.PdfHeaderOptions.HeaderBackColor = Color.WhiteSmoke;

    // Set logo
    ImageElement headerImage = new ImageElement(5, 5, 100, 50, headerImagePath);
    excelToPdfConverter.PdfHeaderOptions.AddElement(headerImage);

    // Set header text
    TextElement headerText = new TextElement(0, 5, "EVO Excel to PDF Converter ",
        new System.Drawing.Font(new System.Drawing.FontFamily("Times New Roman"), 10, System.Drawing.GraphicsUnit.Point));
    // Align the text at the right of the footer
    headerText.TextAlign = HorizontalTextAlign.Right;
    // Set text color
    headerText.ForeColor = Color.Navy;
    // Embed the text element font in PDF
    headerText.EmbedSysFont = true;
    // Add the text element to header
    excelToPdfConverter.PdfHeaderOptions.AddElement(headerText);

    if (drawHeaderLine)
    {
        // Calculate the header width based on PDF page size and margins
        float headerWidth = excelToPdfConverter.PdfDocumentOptions.PdfPageOrientation == PdfPageOrientation.Portrait ?
            excelToPdfConverter.PdfDocumentOptions.PdfPageSize.Width : excelToPdfConverter.PdfDocumentOptions.PdfPageSize.Height -
                    excelToPdfConverter.PdfDocumentOptions.LeftMargin - excelToPdfConverter.PdfDocumentOptions.RightMargin;

        // Calculate header height
        float headerHeight = excelToPdfConverter.PdfHeaderOptions.HeaderHeight;

        // Create a line element for the bottom of the header
        LineElement headerLine = new LineElement(0, headerHeight - 1, headerWidth, headerHeight - 1);

        // Set line color
        headerLine.ForeColor = Color.Gray;

        // Add line element to the bottom of the header
        excelToPdfConverter.PdfHeaderOptions.AddElement(headerLine);
    }
}

/// <summary>
/// Draw the footer elements
/// </summary>
/// <param name="excelToPdfConverter">The Excel to PDF Converter object</param>
/// <param name="addPageNumbers">A flag indicating if the page numbering is present in footer</param>
/// <param name="drawFooterLine">A flag indicating if a line should be drawn at the top of the footer</param>
private void DrawFooter(ExcelToPdfConverter excelToPdfConverter, bool addPageNumbers, bool drawFooterLine)
{
    string footerImagePath = System.IO.Path.Combine(Application.StartupPath,
                @"DemoAppFiles\Input\Images\logo.jpg");

    // Set the footer height in points
    excelToPdfConverter.PdfFooterOptions.FooterHeight = 60;

    // Set footer background color
    excelToPdfConverter.PdfFooterOptions.FooterBackColor = Color.WhiteSmoke;

    // Set logo
    ImageElement headerImage = new ImageElement(5, 5, 100, 50, footerImagePath);
    excelToPdfConverter.PdfFooterOptions.AddElement(headerImage);

    // Add page numbering
    if (addPageNumbers)
    {
        // Create a text element with page numbering place holders &p; and & P;
        TextElement footerText = new TextElement(0, 30, "Page &p; of &P;  ",
            new System.Drawing.Font(new System.Drawing.FontFamily("Times New Roman"), 10, System.Drawing.GraphicsUnit.Point));

        // Align the text at the right of the footer
        footerText.TextAlign = HorizontalTextAlign.Right;

        // Set page numbering text color
        footerText.ForeColor = Color.Navy;

        // Embed the text element font in PDF
        footerText.EmbedSysFont = true;

        // Add the text element to footer
        excelToPdfConverter.PdfFooterOptions.AddElement(footerText);
    }

    if (drawFooterLine)
    {
        // Calculate the footer width based on PDF page size and margins
        float footerWidth = excelToPdfConverter.PdfDocumentOptions.PdfPageOrientation == PdfPageOrientation.Portrait ?
            excelToPdfConverter.PdfDocumentOptions.PdfPageSize.Width : excelToPdfConverter.PdfDocumentOptions.PdfPageSize.Height -
                    excelToPdfConverter.PdfDocumentOptions.LeftMargin - excelToPdfConverter.PdfDocumentOptions.RightMargin;

        // Create a line element for the top of the footer
        LineElement footerLine = new LineElement(0, 0, footerWidth, 0);

        // Set line color
        footerLine.ForeColor = Color.Gray;

        // Add line element to the bottom of the footer
        excelToPdfConverter.PdfFooterOptions.AddElement(footerLine);
    }
}