VB.NET实现DataGridView列分组时报错Type GridViewRow is not defined如何解决

1. 控件API不匹配
   你当前使用的代码是针对ASP.NET Web Forms的GridView控件编写的，而你实际在用的是WinForm的DataGridView控件，二者行对象类型完全不同：

• ASP.NET GridView的行类型是GridViewRow
• WinForm DataGridView的行类型是DataGridViewRow
  你当前项目未引入ASP.NET相关命名空间，自然会抛出Type GridViewRow is not defined的错误。

2. 逻辑不兼容
   即便强行引入ASP.NET命名空间，这段代码也无法在DataGridView上运行，两个控件的单元格属性、合并逻辑的API规则完全不同，必须针对性修改适配。

Protected Sub MergeDuplicateCells()
    ' 从下往上遍历所有行，跳过表头行
    For i As Integer = SearchInvoiceDGV.Rows.Count - 1 To 1 Step -1
        Dim currentRow As DataGridViewRow = SearchInvoiceDGV.Rows(i)
        Dim prevRow As DataGridViewRow = SearchInvoiceDGV.Rows(i - 1)
        ' 遍历所有列
        For j As Integer = 0 To currentRow.Cells.Count - 1
            ' 比较相邻行同一列的内容
            If currentRow.Cells(j).Value?.ToString() = prevRow.Cells(j).Value?.ToString() Then
                ' 用Tag属性存储合并跨度
                If prevRow.Cells(j).Tag Is Nothing Then
                    prevRow.Cells(j).Tag = 1
                End If
                prevRow.Cells(j).Tag = CInt(prevRow.Cells(j).Tag) + 1
                ' 隐藏重复的单元格
                currentRow.Cells(j).Visible = False
            End If
        Next
    Next
End Sub

' 自定义绘制合并单元格，保证内容居中显示完整
Protected Sub SearchInvoiceDGV_CellPainting(sender As Object, e As DataGridViewCellPaintingEventArgs) Handles SearchInvoiceDGV.CellPainting
    If e.RowIndex < 0 OrElse e.ColumnIndex < 0 Then Return
    Dim targetCell = SearchInvoiceDGV.Rows(e.RowIndex).Cells(e.ColumnIndex)
    If targetCell.Tag IsNot Nothing AndAlso CInt(targetCell.Tag) > 1 Then
        ' 去掉合并单元格的下边框
        e.AdvancedBorderStyle.Bottom = DataGridViewAdvancedCellBorderStyle.None
        ' 计算合并后的总高度
        Dim totalHeight As Integer = e.CellBounds.Height
        For spanIndex As Integer = 1 To CInt(targetCell.Tag) - 1
            totalHeight += SearchInvoiceDGV.Rows(e.RowIndex + spanIndex).Height
        Next
        ' 绘制合并后的单元格
        Dim mergeRect As New Rectangle(e.CellBounds.X, e.CellBounds.Y, e.CellBounds.Width, totalHeight)
        e.PaintBackground(mergeRect, True)
        e.PaintContent(mergeRect)
        e.Handled = True
    End If
End Sub

• 如果只需要合并指定列，修改内层循环j的遍历范围到目标列的索引即可
• 在DataGridView完成数据绑定后，手动调用MergeDuplicateCells()即可触发合并效果

内容的提问来源于stack exchange，提问作者Point Systems