c# NPOI 如何在指定单元格导入导出图片

public static Dictionary<CellPosition, IPictureData> GetPicturesAndPosition(this ISheet sheet)
{
  var dictionary = new Dictionary<CellPosition, IPictureData>();
  if (sheet.Workbook is HSSFWorkbook)
  {
    foreach (var shape in ((HSSFPatriarch)sheet.DrawingPatriarch).Children)
    {
      if (shape is HSSFPicture picture)
      {
        var position = new CellPosition(picture.ClientAnchor.Row1, picture.ClientAnchor.Col1);
        dictionary[position] = picture.PictureData;
      }
    }
  }
  else if (sheet.Workbook is XSSFWorkbook)
  {
    foreach (var shape in ((XSSFDrawing)sheet.DrawingPatriarch).GetShapes())
    {
      if (shape is XSSFPicture picture)
      {
        var position = new CellPosition(picture.ClientAnchor.Row1, picture.ClientAnchor.Col1);
        dictionary[position] = picture.PictureData;
      }
    }
  }
  return dictionary;
}

public readonly struct CellPosition : IEquatable<CellPosition>
{
  public CellPosition(int row, int col)
  {
    Row = row;
    Column = col;
  }

  public int Row { get; }
  public int Column { get; }

  public bool Equals(CellPosition other)
  {
    return Row == other.Row && Column == other.Column;
  }

  public override bool Equals(object? obj) => obj is CellPosition other && Equals(other);

  public override int GetHashCode() => $"{Row}_{Column}".GetHashCode();
}

public static bool TryAddPicture(this ISheet sheet, int row, int col, byte[] pictureBytes, PictureType pictureType = PictureType.PNG)
{
  if (sheet is null)
  {
    throw new ArgumentNullException(nameof(sheet));
  }

  try
  {
    var pictureIndex = sheet.Workbook.AddPicture(pictureBytes, pictureType);

    var clientAnchor = sheet.Workbook.GetCreationHelper().CreateClientAnchor();
    clientAnchor.Row1 = row;
    clientAnchor.Col1 = col;

    var picture = (sheet.DrawingPatriarch ?? sheet.CreateDrawingPatriarch())
      .CreatePicture(clientAnchor, pictureIndex);
    picture.Resize();
    return true;
  }
  catch (Exception e)
  {
    Debug.WriteLine(e);
  }

  return false;
}

[Theory]
[ExcelFormatData]
public async Task ImageImportExportTest(ExcelFormat excelFormat)
{
  using var httpClient = new HttpClient();
  var imageBytes = await httpClient.GetByteArrayAsync("https://weihanli.xyz/assets/avator.jpg");
  var list = Enumerable.Range(1, 5)
    .Select(x => new ImageTest() { Id = x, Image = imageBytes })
    .ToList();
  var excelBytes = list.ToExcelBytes(excelFormat);
  var importResult = ExcelHelper.ToEntityList<ImageTest>(excelBytes, excelFormat);
  Assert.NotNull(importResult);
  Assert.Equal(list.Count, importResult.Count);
  for (var i = 0; i < list.Count; i++)
  {
    Assert.NotNull(importResult[i]);
    var result = importResult[i]!;
    Assert.Equal(list[i].Id, result.Id);
    Assert.NotNull(result.Image);
    Assert.True(list[i].Image.SequenceEqual(result.Image));
  }
}

private class ImageTest
{
  public int Id { get; set; }

  public byte[] Image { get; set; } = null!;
}