事件处理程序不使用AddHandler触发

Question

我有一个包含大约40个复选框的表单.选中复选框后,div控件的属性应从"none"更改为"block",反之亦然.我没有收到错误,但未处理checkedchanged事件.这是标记:

<tr>
    <td class="sectionSubHeader lightgrey">
        <asp:CheckBox ID="chkbxCOMAEFund" AutoPostBack="true" runat="server" />
        COM Academic Excellence Fund - Endowed
    </td>
</tr>
<tr>
    <td>
        <ul class="boldDetail">
            <li>Financial Need</li>
        </ul>
    </td>
</tr>
<tr>
    <td colspan="2" class="subSectionPad">Description..</td>
</tr>
<tr>
    <td colspan="2" class="subSectionPad">
        <asp:Label ID="lblCOMAEFund" runat="server"></asp:Label><br />
        <div id="divCOMAEFund" runat="server">
            <asp:TextBox ID="txtCOMAEFund" runat="server" TextMode="MultiLine" Columns="95" Rows="4"></asp:TextBox>
        </div>
    </td>
</tr>

这是代码隐藏:

Dim temp As String
Dim div As HtmlControl

For Each ctrl As Control In wizard.WizardSteps
    For Each subCtrl As Control In ctrl.Controls
        If TypeOf (subCtrl) Is CheckBox Then
            temp = subCtrl.ID.Replace("chkbx", "div")
            div = wizard.FindControl(temp)
            div.Style("display") = "none"
            AddHandler CType(subCtrl, CheckBox).CheckedChanged, AddressOf Chkbx_CheckChanged
        End If
    Next
Next

这是子

Private Sub Chkbx_CheckChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
    Dim temp As String
    temp = sender.ID
    temp = temp.Replace("chkbx", "div")
    Dim divCtrl As HtmlControl
    divCtrl = wizard1.FindControl(temp)

    If sender.Checked = True Then divCtrl.Style("display") = "block" Else divCtrl.Style("display") = "none"

End Sub

Answer 1

您在标记为"代码隐藏"的代码块中附加的事件处理程序仅对页面的迭代有效.处理程序不会在回发中持久存在.因此,当用户选中复选框并且页面自动发回服务器时,事件处理程序尚未连接.

您需要在回发事件处理阶段之前的页面生命周期的某个阶段连接事件处理程序.您可以在PageLoad中或在标记中以声明方式执行此操作.

这是一个类似的问题.