如何使用VB.NET重置DataGridView中的BindingSource/BindingList序列号

Question

我正在尝试使用 VB.NET 重置 DataGridView 中的 BindingSource/BindingList 序列号。

或者我的代码实现出了问题

请指导我。

下面我还附上截图和代码

谢谢

Public Class Form1
    Private bindingSource As BindingSource = Nothing
    Private Function GetProduct() As Product
        Return If(DataGridView1.SelectedCells.Count = 0, Nothing, TryCast(DataGridView1.SelectedCells(0).OwningRow.DataBoundItem, Product))
    End Function
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Dim list = New List(Of Product)() From {
    New Product With {
        .No = 1,
        .Codeproduct = "1000",
        .Qty = 20,
        .Qty_Stock = 50
    },
    New Product With {
            .No = 2,
        .Codeproduct = "2000",
        .Qty = 30,
        .Qty_Stock = 40
    },
     New Product With {
            .No = 3,
        .Codeproduct = "3000",
        .Qty = 30,
        .Qty_Stock = 40
    }
}

 bindingSource = New BindingSource With {.DataSource = New BindingList(Of Product)(CType(list, IList(Of Product)))}
        DataGridView1.DataSource = bindingSource
        DataGridView1.Columns("No").ReadOnly = True
        DataGridView1.Columns("Codeproduct").ReadOnly = True
        DataGridView1.Columns("Qty").ReadOnly = True
        DataGridView1.Columns("Qty_Stock").ReadOnly = True
        DataGridView1.Columns("Coldel").ReadOnly = True
 End Sub

    Private Sub DataGridView1_CellContentClick(sender As Object, e As DataGridViewCellEventArgs) Handles DataGridView1.CellContentClick
        If DataGridView1.Columns(e.ColumnIndex) Is DataGridView1.Columns("Coldel") Then
            If DataGridView1.SelectedRows.Count = 0 Then
                Return
            End If
            If MessageBox.Show("Delete selected record?", "CONFIRM!", MessageBoxButtons.YesNoCancel) = DialogResult.Yes Then
                Dim product = GetProduct()
                Dim bs = TryCast(bindingSource.DataSource, BindingList(Of Product))
                'do method service sql to database
                bs.Remove(product)
                DataGridView1.Refresh()

'update code 
  Dim counter As Integer = 0
                For Each row As DataGridViewRow In DataGridView1.Rows
                    counter += 1
                    'row.Cells("No").Value = counter
row.Cells("No").Value = If(row.Index = DataGridView1.NewRowIndex, Nothing, counter)
                Next row
                'do method service sql save to database




            End If
        End If
    End Sub
End Class

删除前

No

2

删除后

No

2

所以在结果中希望数字 3 成为数字 2

Answer 1

新的网格行显示数据绑定对象的默认值。对于引用类型，如果值什么都没有，新行将不显示任何内容，或者如果您想提供默认值而不是 Nothing/

DbNull

，则显示列

DefaultCellStyle.NullValue

属性的值。

对于像

No

列这样的值类型，数据绑定项的类型为

Integer

，因此，新行显示该类型的默认值

0

。不，您不能在此处使用

NullValue

属性来更改它。

要隐藏

0

列中的默认值

No

，您有两种选择。要么将属性转换为模型中可为空的整数：

Public Class Product
    Public Property No As Integer?
    ' ...
End Class

或设置 DefaultCellStyle.Format 属性来隐藏零值。例如，

#

格式说明符。有关更多信息，请参阅自定义数字格式字符串。

DataGridView1.Columns("No").DefaultCellStyle.Format = "#"