用户控件未获得声明性属性值 [英] User Control not getting declarative property value

问题描述

我在 Web 表单上有一个用户控件，声明如下:

I have a user control on a web form that is declared as follows:

<nnm:DeptDateFilter ID="deptDateFilter" runat="server" AllowAllDepartments="True" />

在此控件的代码隐藏中，AllowAllDepartments 声明如下:

In the code-behind for this control, AllowAllDepartments is declared as follows:

internal bool AllowAllDepartments { get; set; }

然而，当我查看页面并在控件的 Page_Load 事件处理程序中设置断点时，我的 AllowAllDepartments 属性始终为 false.造成这种情况的可能原因是什么?

Yet when I view the page, and set a breakpoint in the control's Page_Load event handler, my AllowAllDepartments property is always false. What are possible reasons for this?

突发新闻:当我在控件的 Page_Load 中遇到断点时，即使以编程方式设置属性也不会影响属性值.这是主机页面的 Page_Load:

BREAKING NEWS: Even setting the property programmatically has no effect on the property value when I hit my breakpoint in Page_Load of the control. Here is the Page_Load of the host page:

deptDateFilter.FilterChanged += deptDateFilter_FilterChanged;
if (!IsPostBack)
{
    deptDateFilter.AllowAllDepartments = true;
    PresentReport();
}

推荐答案

尝试将属性值添加到 ViewState:

Try adding the property value to the ViewState:

protected bool AllowAllDepartments 
{
   get
   {
      if (ViewState["AllowAllDepartments"] != null)
         return bool.Parse(ViewState["AllowAllDepartments"]);
      else
         return false;
   }
   set
   {
      ViewState["AllowAllDepartments"] = value;
   }
}

编辑此外，您可能希望处理控件的 PreRender 事件，以查看控件的属性是否已正确设置.

EDIT Furthermore, you may want to handle the control's PreRender event, to see whether the the control's property has been correctly set there or not.

这篇关于用户控件未获得声明性属性值的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！