c#使用NPOI 256库创建Excel散点图

以下是使用NPOI 2.5.6库创建Excel散点图的示例代码：

using System;
using System.IO;
using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;
using NPOI.SS.Util;
using NPOI.Chart;
using NPOI.Chart.Util;

public class ScatterChartExample
{
    public static void Main(string[] args)
    {
        // Create workbook
        XSSFWorkbook workbook = new XSSFWorkbook();

        // Create worksheet
        ISheet sheet = workbook.CreateSheet("Scatter Chart");

        // Set data for X and Y axis
        IRow row1 = sheet.CreateRow(0);
        row1.CreateCell(0).SetCellValue("X");
        row1.CreateCell(1).SetCellValue("Y");
        for (int i = 1; i <= 10; i++)
        {
            IRow row = sheet.CreateRow(i);
            row.CreateCell(0).SetCellValue(i);
            row.CreateCell(1).SetCellValue(i * i);
        }

        // Create chart
        XSSFDrawing drawing = (XSSFDrawing)sheet.CreateDrawingPatriarch();
        XSSFClientAnchor anchor = drawing.CreateAnchor(0, 0, 0, 0, 4, 0, 15, 15);
        IChart chart = drawing.CreateChart(anchor);

        // Set chart type to scatter chart
        chart.ChartType = NPOI.SS.UserModel.Chart.ChartType.Scatter;

        // Add data to chart
        IChartDataSource<Number> x = DataSources.FromNumericCellRange(sheet, new CellRangeAddress(1, 10, 0, 0));
        IChartDataSource<Number> y = DataSources.FromNumericCellRange(sheet, new CellRangeAddress(1, 10, 1, 1));
        IScatterChartData<Number, Number> data = chart.ChartDataFactory.CreateScatterChartData<Number, Number>(x, y);
        chart.ChartData = data;

        // Set chart title
        IChartTitle chartTitle = chart.Title;
        chartTitle.SetText("Scatter Chart");

        // Set X axis title
        IAxis xAxis = chart.GetChartAxisFactory().CreateCategoryAxis(AxisPosition.Bottom);
        xAxis.Title.SetText("X");

        // Set Y axis title
        IAxis yAxis = chart.GetChartAxisFactory().CreateValueAxis(AxisPosition.Left);
        yAxis.Title.SetText("Y");

        // Save workbook
        FileStream file = new FileStream("ScatterChartExample.xlsx", FileMode.Create);
        workbook.Write(file);
        file.Close();
    }
}

这个示例程序创建一个包含X和Y轴数据的Excel工作表，并使用NPOI 2.5.6库创建一个散点图。程序将数据添加到图表中，设置图表标题，X轴标题和Y轴标题，并将工作簿保存为Excel文件