如何在vb.net中实现OpenXml GradientFill

Imports DocumentFormat.OpenXml
Imports DocumentFormat.OpenXml.Packaging
Imports DocumentFormat.OpenXml.Spreadsheet

Dim workbookPart As WorkbookPart = Nothing
Using document As SpreadsheetDocument = SpreadsheetDocument.Open("YourExcelFile.xlsx", True)
    workbookPart = document.WorkbookPart
End Using

Dim cellFormatIndex As Integer = 0 ' 要进行渐变填充的单元格样式索引
Dim cellFormats As CellFormats = workbookPart.WorkbookStylesPart.Stylesheet.Elements(Of CellFormats).FirstOrDefault()
If cellFormats IsNot Nothing AndAlso cellFormats.Elements(Of CellFormat).Count > 0 Then
    Dim cellFormat As CellFormat = cellFormats.Elements(Of CellFormat).FirstOrDefault(Function(cf) cf.Fill IsNot Nothing AndAlso TypeOf cf.Fill.PatternFill.FillType Is GradientFill)
    If cellFormat IsNot Nothing Then
        cellFormatIndex = cellFormats.Elements(Of CellFormat).ToList().IndexOf(cellFormat)
    End If
End If

Dim gradientFill As New GradientFill()
gradientFill.GradientType = GradientValues.Linear
gradientFill.Degree = 90
gradientFill.Left = 0
gradientFill.Right = 0
gradientFill.Top = 0
gradientFill.Bottom = 0

Dim stop1 As New GradientStop()
stop1.Position = 0
stop1.Color = New Color() With {.Rgb = "FF0000"} ' 渐变填充的起始颜色

Dim stop2 As New GradientStop()
stop2.Position = 1
stop2.Color = New Color() With {.Rgb = "0000FF"} ' 渐变填充的结束颜色

gradientFill.Append(stop1, stop2)

Dim cellFormat As New CellFormat()
cellFormat.Fill = New Fill() With {.GradientFill = gradientFill}

cellFormats.Append(cellFormat)
cellFormats.Count = cellFormats.Elements(Of CellFormat).Count

Dim worksheetPart As WorksheetPart = workbookPart.WorksheetParts.FirstOrDefault()
If worksheetPart IsNot Nothing Then
    Dim sheetData As SheetData = worksheetPart.Worksheet.Elements(Of SheetData).FirstOrDefault()
    If sheetData IsNot Nothing Then
        Dim cell As Cell = sheetData.Descendants(Of Cell).FirstOrDefault(Function(c) c.CellReference.Value = "A1") ' 要进行渐变填充的单元格
        If cell IsNot Nothing Then
            cell.StyleIndex = cellFormatIndex
        End If
    End If
End If

workbookPart.WorkbookStylesPart.Stylesheet.Save()
workbookPart.Workbook.Save()
workbookPart.Package.Close()