How to create waterfall chart with JavaScript via C++

Aspose.Cells APIs allow creating a waterfall chart with the help of the line chart. The API also allows customizing the chart appearance to give it the shape of the waterfall by setting the Series.upBars & Series.downBars properties.

Below provided code snippet demonstrates the usage of Aspose.Cells for JavaScript via C++ to create a waterfall chart from scratch.

<!DOCTYPE html>
<html>
    <head>
        <title>Aspose.Cells Example</title>
    </head>
    <body>
        <h1>Aspose.Cells Chart Waterfall Example</h1>
        <input type="file" id="fileInput" accept=".xls,.xlsx,.csv" />
        <button id="runExample">Run Example</button>
        <a id="downloadLink" style="display: none;">Download Result</a>
        <div id="result"></div>
    </body>

    <script src="aspose.cells.js.min.js"></script>
    <script type="text/javascript">
        const { Workbook, SaveFormat, ChartType, Color, FormattingType } = AsposeCells;
        
        AsposeCells.onReady({
            license: "/lic/aspose.cells.enc",
            fontPath: "/fonts/",
            fontList: [
                "arial.ttf",
                "NotoSansSC-Regular.ttf"
            ]
        }).then(() => {
            console.log("Aspose.Cells initialized");
        });

        document.getElementById('runExample').addEventListener('click', async () => {
            const fileInput = document.getElementById('fileInput');

            // Load workbook from selected file if provided, otherwise create a new workbook
            let workbook;
            if (fileInput.files && fileInput.files.length > 0) {
                const file = fileInput.files[0];
                const arrayBuffer = await file.arrayBuffer();
                workbook = new Workbook(new Uint8Array(arrayBuffer));
            } else {
                workbook = new Workbook();
            }

            // Retrieve the first Worksheet in Workbook
            const worksheet = workbook.worksheets.get(0);

            // Retrieve the Cells of the first Worksheet
            const cells = worksheet.cells;

            // Input some data which chart will use as source
            cells.get("A1").value = "Previous Year";
            cells.get("A2").value = "January";
            cells.get("A3").value = "March";
            cells.get("A4").value = "August";
            cells.get("A5").value = "October";
            cells.get("A6").value = "Current Year";

            cells.get("B1").value = 8.5;
            cells.get("B2").value = 1.5;
            cells.get("B3").value = 7.5;
            cells.get("B4").value = 7.5;
            cells.get("B5").value = 8.5;
            cells.get("B6").value = 3.5;

            cells.get("C1").value = 1.5;
            cells.get("C2").value = 4.5;
            cells.get("C3").value = 3.5;
            cells.get("C4").value = 9.5;
            cells.get("C5").value = 7.5;
            cells.get("C6").value = 9.5;

            // Add a Chart of type Waterfall in same worksheet as of data
            const idx = worksheet.charts.add(ChartType.Waterfall, 4, 4, 25, 13);

            // Retrieve the Chart object
            const chart = worksheet.charts.get(idx);

            // Add Series
            chart.nSeries.add("$B$1:$C$6", true);

            // Add Category Data
            chart.nSeries.categoryData = "$A$1:$A$6";

            // Series has Up Down Bars
            chart.nSeries.get(0).hasUpDownBars = true;

            // Set the colors of Up and Down Bars
            chart.nSeries.get(0).upBars.area.foregroundColor = Color.Green;
            chart.nSeries.get(0).downBars.area.foregroundColor = Color.Red;

            // Make both Series Lines invisible
            chart.nSeries.get(0).border.isVisible = false;
            chart.nSeries.get(1).border.isVisible = false;

            // Set the Plot Area Formatting Automatic
            chart.plotArea.area.formatting = FormattingType.Automatic;

            // Delete the Legend
            chart.legend.legendEntries.get(0).isDeleted = true;
            chart.legend.legendEntries.get(1).isDeleted = true;

            // Save the workbook
            const outputData = workbook.save(SaveFormat.Xlsx);
            const blob = new Blob([outputData]);
            const downloadLink = document.getElementById('downloadLink');
            downloadLink.href = URL.createObjectURL(blob);
            downloadLink.download = 'output_out.xlsx';
            downloadLink.style.display = 'block';
            downloadLink.textContent = 'Download Excel File';

            document.getElementById('result').innerHTML = '<p style="color: green;">Operation completed successfully! Click the download link to get the modified file.</p>';
        });
    </script>
</html>