無法獲取asp.net中動態添加的用戶控件的值

Question

這是在我的用戶控件中

<div class=" row-fluid">
<div class="span4" style="overflow: hidden;">
    <asp:DropDownList ID="ddlAccountName" runat="server" DataSourceID="ChartOfAccountsforVouchers"
        DataTextField="AccountName" DataValueField="ChartOfAccID">
    </asp:DropDownList>
   <%-- <asp:EntityDataSource ID="ChartOfAccountsforVouchers" runat="server" ConnectionString="name=CnFV1MainModelEntities"
        DefaultContainerName="CnFV1MainModelEntities" EnableFlattening="False" EntitySetName="ChartOfAccounts"
        Select="it.[ChartOfAccID], it.[AccountName]">
    </asp:EntityDataSource>--%>
</div>
<div class="span4">
    <asp:TextBox ID="txtValue" MaxLength="10" CssClass="numeric input-block-level" runat="server"></asp:TextBox>
</div>
<div class="span4">
    <asp:TextBox ID="txtValueB" MaxLength="10" CssClass="numeric input-block-level" runat="server"></asp:TextBox>
</div>

這就是我將此控件添加到占位符的方式

int count = Convert.ToInt32(Session["AddedRows"]);
        ++count;
        for (int i = 0; i < count; i++)
        {
            // Add the usercontrol dynamically
            Control webUserControl = (Control)Page.LoadControl("ctrlEntryRows.ascx");
            placeRows.Controls.Add(webUserControl);
        }

        Session["AddedRows"] = count.ToString();

這就是單擊按鈕時我試圖獲取控件的方式

if (placeRows.Controls.Count > 0)
            {
                foreach (Control ctrl in placeRows.Controls)
                {
                    TextBox txt = (TextBox)placeRows.FindControl("txtValue");
                    TextBox txtB = (TextBox)placeRows.FindControl("txtValueB");
                    string message = txt.Text + txtB.Text;
                }
            }

但是代碼顯示為0 count.IT甚至沒有進入循環。 如何獲得動態添加的用戶控件的值？

謝謝

Answer 1

嘗試這個

if (placeRows.Controls.Count > 0)
            {
                foreach (Control ctrl in placeRows.Controls)
                {
                    TextBox txt = (TextBox)ctrl.FindControl("txtValue");
                    TextBox txtB = (TextBox)ctrl.FindControl("txtValueB");
                    string message = txt.Text + txtB.Text;
                }
            }

更新：

您應該閱讀諸如此類的有關動態控件和狀態管理的文章。

1. http://www.codeproject.com/Articles/3684/Retaining-State-for-Dynamically-Created-Controls-i
2. http://www.4guysfromrolla.com/articles/092904-1.aspx
3. 維持回發時動態添加的用戶控件的狀態？