Question

这是非常重要的问题。这让我疯狂4小时:(我可以加载UCAddX.ascx，但如果我点击“在X中搜索”按钮不加载UCSearchX用户控件。有3个按钮也有3个Web用户控件。我想加载这3个web clickEvents之后的用户控件。但是下面的方法不能正常工作。如何动态加载Web用户控件？单击按点击（如Tab控件）

 public partial class MyPage: System.Web.UI.Page
    {
   protected void Page_Load(object sender, EventArgs e)
        {
            ViewState["controlType"] = "AddX";
            if (!IsPostBack)
            {
                AddUserControl();
            }
            else
            {
                AddUserControl();
            }
        }

        protected void btnAddX_Click(object sender, DirectEventArgs e)
        {
            ViewState["controlType"] = "AddX";
            if (!IsPostBack)
                  AddUserControl();
            else
                AddUserControl();
        }

        protected void btnSearchX_Click(object sender, DirectEventArgs e)
        {
            ViewState["controlType"] = "SearchX";
            if (!IsPostBack)
                AddUserControl();
            else
                AddUserControl();

        }
        protected void btnUpdateX_Click(object sender, DirectEventArgs e)
        {

        }

        void AddUserControl()
        {
          //  plhContent1.Controls.Clear();
            if (ViewState["controlType"] != null)
            {
                if (ViewState["controlType"].ToString() == "AddX")
                {
                    UCAddX uc = (UCAddX)Page.LoadControl("~/Pages/EN/MyUserControls/UCAddX.ascx");
                    uc.ID = "ucAddX";
                    uc.Attributes.Add("runat", "Server");
                    uc.EnableViewState = true;
                    uc.Visible = true;
                    plhContent1.Controls.Add(uc);
                }
                else if (ViewState["controlType"].ToString() == "SearchX")
                {
                    UCSearchX uc = (UCSearchX)Page.LoadControl("~/Pages/EN/MyUserControls/UCSearchX.ascx");
                    uc.ID = "ucSearchX";
                    uc.Attributes.Add("runat", "Server");
                    uc.EnableViewState = true;
                    uc.Visible = true;
                    plhContent1.Controls.Add(uc);
                }


            }
        }

    }

Answer 1

使用以下代码动态加载usercontrol

var control = LoadControl(filePath) as ControlType;

然后您可以订阅事件并添加到控件占位符。

希望这有帮助

Answer 2

尝试这样的事情，

//to load the control
     protected void Page_Init(object sender, EventArgs e)
     {
         ViewState["controlType"] = "AddSector";
         //you don't need to check the if condiontion, cause you load every time the controls
         AddUserControl();
      }

当您需要在回发后从控件获取值时，您应该在

上获取它

protected void Page_PreRender(object sender, EventsArgs args) {
    //your placeholder that contains data
}

Answer 3

动态加载时的用户控件需要在每个Page_Load上加载，以便维护其视图状态。所以你需要这样的东西：

    public string CurrentControlToLoad
    {
        get
        {
             if(ViewState["controlType"] == null)
                 return "";
             return (string)ViewState["controlType"];
        }
        set
        {
             ViewState["controlType"] = value;
        }
    }

    protected void Page_Load(object sender, EventArgs e)
    {
        if(CurrentControlToLoad != "")
           LoadControl(CurrentControlToLoad);
    }

    protected void btnAddSector_Click(object sender, DirectEventArgs e)
    {
        CurrentControlToLoad = "AddSector";
        LoadControl(CurrentControlToLoad);
    }

如何动态加载Web用户控件？

3 个答案: