asp.net - gridview 循环问题

Question

我有一个 4 列的 gridview，其中三个是模板字段，用户可以在其中输入所需的信息，然后单击按钮将其提交到数据库。我有两个问题：

1. 当我单击按钮添加第二行时……第一行帖子中的数据
   消失了。我希望能够添加该行，而不会因多条记录输入情况而第一行信息消失。我的代码如下：

   Private Sub SetInitialRow()
       Dim dts As New DataTable()
       Dim drs As DataRow = Nothing
       dts.Columns.Add(New DataColumn("Approval Date", GetType(String)))
       dts.Columns.Add(New DataColumn("Total Amount", GetType(String)))
       dts.Columns.Add(New DataColumn("Comments", GetType(String)))
       dts.Columns.Add(New DataColumn("Initials", GetType(String)))
       drs = dts.NewRow()
       drs("Approval Date") = String.Empty
       drs("Total Amount") = String.Empty
       drs("Comments") = String.Empty
       drs("Initials") = String.Empty
       dts.Rows.Add(drs)
       ViewState("CurrentTable") = dts
       gvOLIAdj.DataSource = dts
       gvOLIAdj.DataBind()
   End Sub
   
   Private Sub AddNewRowToGrid()
       Dim rowIndex As Integer = 0
       If ViewState("CurrentTable") IsNot Nothing Then
           Dim dtCurrentTable As DataTable = DirectCast(ViewState("CurrentTable"), DataTable)
           Dim drCurrentRow As DataRow = Nothing
           If dtCurrentTable.Rows.Count > 0 Then
               For i As Integer = 1 To dtCurrentTable.Rows.Count
                   'extract the TextBox values
                   Dim box1 As TextBox = DirectCast(gvOLIAdj.Rows(rowIndex).Cells(1).FindControl("txtAdjAppr"), TextBox)
                   Dim box2 As TextBox = DirectCast(gvOLIAdj.Rows(rowIndex).Cells(2).FindControl("txtAdjAmt"), TextBox)
                   Dim box3 As TextBox = DirectCast(gvOLIAdj.Rows(rowIndex).Cells(3).FindControl("txtCmmts"), TextBox)
                   drCurrentRow = dtCurrentTable.NewRow()
                   drCurrentRow("Approval Date") = box1.Text
                   dtCurrentTable.Rows(i - 1)("Total Amount") = box2.Text
                   dtCurrentTable.Rows(i - 1)("Comments") = box3.Text
                   'dtCurrentTable.Rows(i - 1)("Initials") = 
                   rowIndex += 1
               Next
               dtCurrentTable.Rows.Add(drCurrentRow)
               ViewState("CurrentTable") = dtCurrentTable
               gvOLIAdj.DataSource = dtCurrentTable
               gvOLIAdj.DataBind()
           End If
       Else
           Response.Write("ViewState is null")
       End If
       'Set Previous Data on Postbacks
       SetPreviousData()
   End Sub
   
   Private Sub SetPreviousData()
       Dim rowIndex As Integer = 0
       If ViewState("CurrentTable") IsNot Nothing Then
           Dim dats As DataTable = DirectCast(ViewState("CurrentTable"), DataTable)
           If dats.Rows.Count > 0 Then
               For i As Integer = 0 To dats.Rows.Count - 1
                   Dim box1 As TextBox = DirectCast(gvOLIAdj.Rows(rowIndex).Cells(1).FindControl("txtAdjAppr"), TextBox)
                   Dim box2 As TextBox = DirectCast(gvOLIAdj.Rows(rowIndex).Cells(2).FindControl("txtAdjAmt"), TextBox)
                   Dim box3 As TextBox = DirectCast(gvOLIAdj.Rows(rowIndex).Cells(3).FindControl("txtCmmts"), TextBox)
                   box1.Text = dats.Rows(i)("Approval Date").ToString()
                   box2.Text = dats.Rows(i)("Total Amount").ToString()
                   box3.Text = dats.Rows(i)("Comments").ToString()
                   rowIndex += 1
               Next
           End If
       End If
   End Sub
   
   Protected Sub btnAddNewRow_Click(sender As Object, e As EventArgs) Handles btnAddNewRow.Click
       AddNewRowToGrid()
   
   End Sub
   

2. 当我尝试编写一个循环来遍历每个模板字段以获取数据并将其放入我的数据库时，它无法识别我在模板字段中有数据？这是我迄今为止尝试过的无济于事......

   Protected Sub btn_Update_Click(sender As Object, e As EventArgs) Handles btn_Update.Click
       For Each row As GridViewRow In gvOLIAdj.Rows
           For Each gv As GridViewRow In gvOLIAdj.Rows
               Dim appDt As String = (Rows(rowIndex).Cells(1).FindControl("txtAdjAppr")), TextBox)
               Dim approvalDt As String = CType(gv.FindControl("txtAdjAppr"), TextBox).Text
               Dim totalAmt As String = CType(gv.FindControl("txtAdjAmt"), TextBox).Text
               Dim comments As String = CType(gv.FindControl("txtcmmts"), TextBox).Text
               Dim intitials As String = DirectCast(gv.FindControl("total"), TextBox).Text
       Next
   
   End Sub 
   

Answer 1

在您的 AddNewRowToGrid 方法中，您正在执行以下操作：

            dtCurrentTable.Rows(i - 1)("Total Amount") = box2.Text
            dtCurrentTable.Rows(i - 1)("Comments") = box3.Text

这里的问题是更新 dtCurrentTable.Rows( i - 1 ) 中的行。您正在更新要更新的值上方的行中的值。