ASP.NET公共属性ViewState

Question

我正在生成一个总计来自转发器的一些列并将其放入转发器的页脚的报告。

我已经通过设置一个公共属性为如下每个总价值做到了这一点：

Public Property [CostTotal] As Decimal 
    Get 
     Return CStr(ViewState("CostTotal")) 
    End Get 
    Set(ByVal value As Decimal) 
     ViewState("CostTotal") = value 
    End Set 
End Property 

有对报告中的一些过滤选项，使用户可以选择日期等，以滤除报告。

当有人这样做时，公共属性值仍然保留（因为它在视图状态）设置的任何过滤器，因此总数不会累加。有没有办法将公共属性重新设置为0，如果页面被重新发布或者完全采用这种方式？

的ItemDataBound代码

Protected Sub reMileage_ItemDataBound(sender As Object, e As System.Web.UI.WebControls.RepeaterItemEventArgs) Handles reMileage.ItemDataBound 



    If e.Item.ItemType = ListItemType.Item OrElse e.Item.ItemType = ListItemType.AlternatingItem Then 

     Dim rowView As System.Data.DataRowView 
     rowView = CType(e.Item.DataItem, System.Data.DataRowView) 


     Dim lMileageDate As Literal = CType(e.Item.FindControl("lMileageDate"), Literal) 
     If Not IsDBNull(rowView("Date")) Then 
      Dim MileageDate As Date = rowView("Date") 
      lMileageDate.Text = MileageDate.ToString("dd/MM/yyyy") 
     End If 

     Dim lMileageDescription As Literal = CType(e.Item.FindControl("lMileageDescription"), Literal) 
     If Not IsDBNull(rowView("Location")) Then 
      lMileageDescription.Text = Format.TextboxHtmlDecode(rowView("Location")) 
     End If 

     Dim lMileageRate As Literal = CType(e.Item.FindControl("lMileageRate"), Literal) 
     If Not IsDBNull(rowView("Rate")) Then 
      Dim MileageRate As Decimal = rowView("Rate") 
      lMileageRate.Text = MileageRate.ToString("N3") 
     End If 

     Dim lMileageMiles As Literal = CType(e.Item.FindControl("lMileageMiles"), Literal) 
     If Not IsDBNull(rowView("Mileage")) Then 
      Dim MileageMiles As Decimal = rowView("Mileage") 
      lMileageMiles.Text = MileageMiles.ToString("N2") 

      MileageTotal += MileageMiles 
      'Response.Write(MileageTotal & "<br>" & MileageMiles) 
     End If 


     Dim lMileageCost As Literal = CType(e.Item.FindControl("lMileageCost"), Literal) 
     If Not IsDBNull(rowView("Cost")) Then 
      Dim MileageCost As Decimal = rowView("Cost") 
      lMileageCost.Text = MileageCost.ToString("C2") 

      CostTotal += MileageCost 
     End If 


    ElseIf e.Item.ItemType = ListItemType.Footer Then 


     Dim lMileageTotal As Literal = CType(e.Item.FindControl("lMileageTotal"), Literal) 
     lMileageTotal.Text = MileageTotal.ToString("N2") 

     Dim lCostTotal As Literal = CType(e.Item.FindControl("lCostTotal"), Literal) 
     lCostTotal.Text = CostTotal.ToString("C2") 

    End If 

End Sub 

感谢您的帮助。 J.

Answer 1

你可以试试这个方法：

Protected Sub reMileage_ItemDataBound(sender As Object, e As System.Web.UI.WebControls.RepeaterItemEventArgs) Handles reMileage.ItemDataBound 

    If e.Item.ItemType = ListItemType.Header Then 
     CostTotal =0 

    ElseIf e.Item.ItemType = ListItemType.Item OrElse e.Item.ItemType = ListItemType.AlternatingItem Then 

     Dim rowView As System.Data.DataRowView 
     rowView = CType(e.Item.DataItem, System.Data.DataRowView) 


     Dim lMileageDate As Literal = CType(e.Item.FindControl("lMileageDate"), Literal) 
     If Not IsDBNull(rowView("Date")) Then 
      Dim MileageDate As Date = rowView("Date") 
      lMileageDate.Text = MileageDate.ToString("dd/MM/yyyy") 
     End If 

     Dim lMileageDescription As Literal = CType(e.Item.FindControl("lMileageDescription"), Literal) 
     If Not IsDBNull(rowView("Location")) Then 
      lMileageDescription.Text = Format.TextboxHtmlDecode(rowView("Location")) 
     End If 

     Dim lMileageRate As Literal = CType(e.Item.FindControl("lMileageRate"), Literal) 
     If Not IsDBNull(rowView("Rate")) Then 
      Dim MileageRate As Decimal = rowView("Rate") 
      lMileageRate.Text = MileageRate.ToString("N3") 
     End If 

     Dim lMileageMiles As Literal = CType(e.Item.FindControl("lMileageMiles"), Literal) 
     If Not IsDBNull(rowView("Mileage")) Then 
      Dim MileageMiles As Decimal = rowView("Mileage") 
      lMileageMiles.Text = MileageMiles.ToString("N2") 

      MileageTotal += MileageMiles 
      'Response.Write(MileageTotal & "<br>" & MileageMiles) 
     End If 


     Dim lMileageCost As Literal = CType(e.Item.FindControl("lMileageCost"), Literal) 
     If Not IsDBNull(rowView("Cost")) Then 
      Dim MileageCost As Decimal = rowView("Cost") 
      lMileageCost.Text = MileageCost.ToString("C2") 

      CostTotal += MileageCost 
     End If 


    ElseIf e.Item.ItemType = ListItemType.Footer Then 


     Dim lMileageTotal As Literal = CType(e.Item.FindControl("lMileageTotal"), Literal) 
     lMileageTotal.Text = MileageTotal.ToString("N2") 

     Dim lCostTotal As Literal = CType(e.Item.FindControl("lCostTotal"), Literal) 
     lCostTotal.Text = CostTotal.ToString("C2") 

    End If 

End Sub