如何在同一个datagridview中拖放行

Question

在Windows应用程序（Visual Studio）（VB）中，如何将单个行拖放到另一个帖子以允许用户重新排序该行？ 我还没有找到任何有价值的例子。

Answer 1

这是来自这个C＃答案的vb版本： 我怎样才能将DataGridView行拖放到彼此之下？

表单类变量：

Private fromIndex As Integer
Private dragIndex As Integer
Private dragRect As Rectangle

拖动事件：

Private Sub DataGridView1_DragDrop(ByVal sender As Object, _
                                   ByVal e As DragEventArgs) _
                                   Handles DataGridView1.DragDrop
  Dim p As Point = DataGridView1.PointToClient(New Point(e.X, e.Y))
  dragIndex = DataGridView1.HitTest(p.X, p.Y).RowIndex
  If (e.Effect = DragDropEffects.Move) Then
    Dim dragRow As DataGridViewRow = e.Data.GetData(GetType(DataGridViewRow))
    DataGridView1.Rows.RemoveAt(fromIndex)
    DataGridView1.Rows.Insert(dragIndex, dragRow)
  End If
End Sub

Private Sub DataGridView1_DragOver(ByVal sender As Object, _
                                   ByVal e As DragEventArgs) _
                                   Handles DataGridView1.DragOver
  e.Effect = DragDropEffects.Move
End Sub

鼠标事件：

Private Sub DataGridView1_MouseDown(ByVal sender As Object, _
                                    ByVal e As MouseEventArgs) _
                                    Handles DataGridView1.MouseDown
  fromIndex = DataGridView1.HitTest(e.X, e.Y).RowIndex
  If fromIndex > -1 Then
    Dim dragSize As Size = SystemInformation.DragSize
    dragRect = New Rectangle(New Point(e.X - (dragSize.Width / 2), _
                                       e.Y - (dragSize.Height / 2)), _
                             dragSize)
  Else
    dragRect = Rectangle.Empty
  End If
End Sub

Private Sub DataGridView1_MouseMove(ByVal sender As Object, _
                                    ByVal e As MouseEventArgs) _
                                    Handles DataGridView1.MouseMove
  If (e.Button And MouseButtons.Left) = MouseButtons.Left Then
    If (dragRect <> Rectangle.Empty _
    AndAlso Not dragRect.Contains(e.X, e.Y)) Then
      DataGridView1.DoDragDrop(DataGridView1.Rows(fromIndex), _
                               DragDropEffects.Move)
    End If
  End If
End Sub

确保将网格AllowDrop属性设置为true。

Answer 2

更新：

代替

 If dragIndex < 0 Then dragIndex = DataGridView1.RowCount - 1

改成

 If dragIndex > -1 Then 
      'action if not selected in the row header and blank space
 else
      'return error if selected in the column header and blank space
 end if

当你将一行拖到“空白区域”时会出现错误，如果你不相信我，你必须尝试一下。

最终代码（仅用于“拖动事件”部分）是这样的：

  Private Sub DataGridView1_DragDrop(ByVal sender As Object, ByVal e As DragEventArgs) Handles DataGridView1.DragDrop
        Dim p As Point = DataGridView1.PointToClient(New Point(e.X, e.Y))
        dragIndex = DataGridView1.HitTest(p.X, p.Y).RowIndex
    'Determine if dragindex is valid row index       
    If dragIndex > -1 Then
        If (e.Effect = DragDropEffects.Move) Then
            Dim dragRow As DataGridViewRow = CType(e.Data.GetData(GetType(DataGridViewRow)), DataGridViewRow)
            DataGridView1.Rows.RemoveAt(fromIndex)
            DataGridView1.Rows.Insert(dragIndex, dragRow)
            'Add this line of code if you want to put selected rows to the rows that change
            DataGridView1.Rows(dragIndex).Selected = True
        End If 
       Else 'Do any message here if selected in column header and blank space. 
       End If
    End Sub

Answer 3

这是一个没有上述错误的控件。

在Windows窗体设计器AllowDrop AllowUserToOrderRows和AllowDrop设置为True并拖动行标题，而不是内容。

Imports System.ComponentModel

Public Class BetterDataGridView
    Inherits DataGridView

    <Category("Behavior"), DefaultValue(False)>
    Public Property AllowUserToOrderRows As Boolean = False

    Protected Overrides Sub OnMouseDown(e As MouseEventArgs)
        MyBase.OnMouseDown(e)

        Dim hitInfo As HitTestInfo = HitTest(e.X, e.Y)
        If AllowUserToOrderRows AndAlso
                e.Button = MouseButtons.Left AndAlso
                hitInfo.ColumnIndex = -1 AndAlso
                ValidRow(hitInfo.RowIndex) Then
            DoDragDrop(Rows(hitInfo.RowIndex), DragDropEffects.Move)
        End If
    End Sub

    Protected Overrides Sub OnDragOver(e As DragEventArgs)
        MyBase.OnDragOver(e)

        Dim dragRow As DataGridViewRow = e.Data.GetData(GetType(DataGridViewRow))
        Dim targetIndex As Integer = GetRowIndex(e)
        e.Effect = If(ValidRowDragDrop(dragRow, targetIndex),
                      DragDropEffects.Move,
                      DragDropEffects.None)
    End Sub

    Protected Overrides Sub OnDragDrop(e As DragEventArgs)
        MyBase.OnDragDrop(e)

        Dim dragRow As DataGridViewRow = e.Data.GetData(GetType(DataGridViewRow))
        Dim targetIndex As Integer = GetRowIndex(e)

        If e.Effect = DragDropEffects.Move AndAlso ValidRowDragDrop(dragRow, targetIndex) Then
            EndEdit()

            Rows.Remove(dragRow)
            Rows.Insert(targetIndex, dragRow)

            ClearSelection()
            dragRow.Selected = True
        End If
    End Sub

    Protected Function ValidRow(rowIndex As Integer) As Boolean
        Return rowIndex >= 0 AndAlso
            rowIndex < Rows.Count - If(AllowUserToAddRows, 1, 0)
    End Function

    Protected Function GetRowIndex(e As DragEventArgs) As Integer
        Dim clientPos As Point = PointToClient(New Point(e.X, e.Y))
        Return HitTest(clientPos.X, clientPos.Y).RowIndex
    End Function

    Protected Function ValidRowDragDrop(dragRow As DataGridViewRow, targetIndex As Integer) As Boolean
        Return dragRow IsNot Nothing AndAlso
            ValidRow(targetIndex) AndAlso
            targetIndex <> dragRow.Index AndAlso
            Rows.Contains(dragRow)
    End Function
End Class

Answer 4

谢谢你的一切，代码工作。 我只得到一个错误。 我解决了

如果设置了datagridview“启用编辑”，则在抛出行间距时会收到错误。 你可以试试。 我解决了如下：

    Private Sub DataGridView1(ByVal sender As Object, ByVal e As DragEventArgs) Handles DataGridView1.DragDrop

    Dim p As Point = DataGridView1.PointToClient(New Point(e.X, e.Y))
                    dragIndex = DataGridView1.HitTest(p.X, p.Y).RowIndex
                    If (e.Effect = DragDropEffects.Move) Then
                        Dim dragRow As DataGridViewRow = CType(e.Data.GetData(GetType(DataGridViewRow)), DataGridViewRow)

                        If dragIndex = DataGridView1.RowCount - 1 Then '**ADD THIS AREA**
                            DataGridView1.Rows.RemoveAt(fromIndex)
                            DataGridView1.Rows.Insert(DataGridView1.RowCount - 1, dragRow)
                        Else
                            If dragIndex < 0 Then dragIndex = DataGridView1.RowCount - 2 '**this is important**
                            DataGridView1.Rows.RemoveAt(fromIndex)
                            DataGridView1.Rows.Insert(dragIndex, dragRow)
                        End If
                    End If
End Sub

感谢所有其他信息

Answer 5

1.5事件GridView.DragDrop的改进：

1. 前50％的改进，为避免描述错误，您也可以使用

    Private Sub DgvSearchFieldCurrent_DragDrop( _ ByVal sender As Object, ByVal e As DragEventArgs) _ Handles DgvSearchFieldCurrent.DragDrop Dim LclDgv As DataGridView = CType(sender, DataGridView) If dragIndex > -1 AndAlso dragIndex < LclDgv.RowCount -1 Then 

2. 第二是将焦点设置为当前行和第一个单元格：

    LclDgv.Rows.Insert(dragIndex, dragRow) LclDgv.Rows(fromIndex).Selected = False LclDgv.Rows(dragIndex).Selected = True For Each C As DataGridViewColumn In LclDgv.Columns LclDgv(C.Index, fromIndex).Selected = False Next LclDgv(0, dragIndex).Selected = True