设置具有多个实例的usercontrol的一次性属性值

Question

我在页面中有多个实例的user control。在page.aspx函数page_load中，我知道是否要在该控件中为该控件的所有实例显示或隐藏某些内容。在我的页面中，我有包含此usercontrol的usercontrols。

对于每个页面，都有另一个条件来显示或隐藏该控件中的某些内容-（属性不能是静态的…）

我正在寻找一个正确的解决方案。。谢谢

ToPostFloorType floor = new ToPostFloorType();
UserControl uc;
DataTable floors;
floors = floor.FetchFloorTypesByPageID(pageID, iActiveVersion, iWithHeadAndFooter);
for (int i = 0; i < floors.Rows.Count; i++)
{
    try
    {
        PlaceHolder phFloors = this.Page.FindControl("PlaceHolderFloors") as PlaceHolder;
        uc = this.LoadControl("~" + floors.Rows[i]["FloorAscxPrefix"].ToString()) as UserControl;
        uc.ID = floors.Rows[i]["PageTypeFloorTypeID"].ToString();
        uc.EnableViewState = false;
        phFloors.Controls.Add(uc);
    }
    catch (Exception ex)
    {
        throw;
    }
}

Answer 1

您可以使用此递归扩展方法来查找此控件的所有引用：

public static IEnumerable<Control> GetControlsRecursively(this Control parent)
{
    foreach (Control c in parent.Controls)
    {
        yield return c;
        if (c.HasControls())
        {
            foreach (Control control in c.GetControlsRecursively())
            {
                yield return control;
            }
        }
    }
}

现在使用Enumerable.OfType:很容易

protected void Page_Load(Object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        // presuming the type of your control is MyUserControl
        var allUCs = this.GetControlsRecursively().OfType<MyUserControl>();
        foreach (MyUserControl uc in allUCs)
        {
            // do something with it
        }
    }
}