Question

在CodeBehind类中，我有这个：

Public Class MyControl
    Inherits UserControl

    ' Is used in other functions so cannot be hardcoded:
    Public Enum TabID
        Accepted = 138
        Declined = 139
        Unknown = 140
        InProgress = 141
    End Enum

    Public Sub Tab_OnClick(sender As Object, e As EventArgs)

        Dim selectedTabID As Integer
        Dim linkBtn As LinkButton

        If Page.IsPostBack Then

            linkBtn = CType(sender, LinkButton)
            selectedTabID = CType(linkBtn.CommandArgument, Integer)

            ' Do stuff with selectedTabID...

        End If

    End Sub

    ' More irrelevant code...

End Class

在ascx文件中（前面的代码？）我有这个：

<asp:LinkButton id="AcceptedTab" Runat="server" Text="Accepted" CssClass="selected"
    CommandArgument="<%# TabID.Accepted %>" OnClick="Tab_OnClick"/>

问题是，行selectedTabID = CType(linkBtn.CommandArgument, Integer)显示调试期间linkBtn.CommandArgument是一个空字符串（应该是＆＃34; 138＆＃34;）并且它无法将空字符串转换为整数在运行期间。

我还试过将enum转换为ascx文件中的整数：

<asp:LinkButton id="AcceptedTab" Runat="server" Text="Accepted" CssClass="selected"
    CommandArgument="<%# CInt(TabID.Accepted) %>" OnClick="Tab_OnClick"/>

如何使用此方法在Tab_OnClick函数中获取此枚举值？

Answer 1

您需要在Page Load上调用DataBind()，因为您要将数据绑定到<%#的LinkButton。

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)        
    DataBind
End Sub

其次，切换到Command，而不是Click。然后您可以直接访问CommandArgument

<asp:LinkButton id="AcceptedTab" Runat="server" Text="Accepted" CssClass="selected"
   CommandArgument="<%# CInt(TabID.Accepted) %>" OnCommand="AcceptedTab_Command"/>

在代码背后。

Protected Sub AcceptedTab_Command(ByVal sender As Object, ByVal e As CommandEventArgs)
    Dim arg As String = e.CommandArgument.ToString
End Sub

无法在CommandArgument中为WebForms传递枚举值

1 个答案: