c# - 当前上下文中不存在名称 'txtStudentDOB'

Question

我有一个 Web 表单用户控件，我想在编辑表单中将日历添加到文本框，但是我在 void Calendar1_SelectionChanged1(object sender, EventArgs e ) 。问题是我无法从编辑表单上下文访问日历。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Globalization;

namespace LearningSystem.Controls
{
 public partial class usrStudent : System.Web.UI.UserControl
{
    protected void Page_Load(object sender, EventArgs e) 
    {
        if (!IsPostBack)
        {
            Calendar1.Visible = false;
        }

    }
    protected void ImageButton1_Click(object sender, ImageClickEventArgs e)
    {
        if (Calendar1.Visible == false)
        {
            Calendar1.Visible = true;
        }
        else
        {
            Calendar1.Visible = true;
        }
    }

     void Calendar1_SelectionChanged1(object sender, EventArgs e)
    {
        txtStudentDOB.Text = Calendar1.SelectedDate.ToShortDateString();
        Calendar1.Visible = false;
    }
 }

这里是HTML代码

 <asp:FormView ID="frmStudent" runat="server" DataSourceID="odsStudent" Width="100%" OnItemDeleted="frmStudent_ItemDeleted" DataKeyNames="StudentID" OnItemInserted="frmStudent_ItemInserted" OnItemUpdated="frmStudent_ItemUpdated" >
<EditItemTemplate>

                <asp:TextBox ID="txtStudentDOB" runat="server" CssClass="form-control" Text='<%# Bind("StudentDOB" , "{0:d}") %>'  />
                <asp:ImageButton ID="ImageButton1" runat="server" OnClick="ImageButton1_Click" />
                <asp:RequiredFieldValidator ID="RequiredFieldValidator12" runat="server" Display="Dynamic" ControlToValidate="txtStudentDOB" ErrorMessage="Please Enter Date of Birth" ForeColor="Red">*</asp:RequiredFieldValidator>
                <asp:RangeValidator ID ="rvDate" runat ="server" C
                &nbsp;</div>
        </div>

        <div class="col-md-offset-2 col-md-10"">
        <asp:LinkButton ID="btnUpdate" runat="server" CssClass="btn btn-success" CausesValidation="True" CommandName="Update" Text="Update" OnClick="btnUpdate_Click" />
        &nbsp;<asp:LinkButton ID="btnCancel" runat="server" CausesValidation="False" CommandName="Cancel" Text="Cancel" Font-Bold="false" />
    </div>
    </div>
</EditItemTemplate>

<asp:Calendar ID="Calendar1" runat="server" OnSelectionChanged="Calendar1_SelectionChanged1" >          </asp:Calendar>

Answer 1

您不能直接访问窗体 View 中的控件。您需要在表单 View 中找到它。试试下面的代码

void Calendar1_SelectionChanged1(object sender, EventArgs e)
{
   TextBox txtStudentDOB = frmStudent.FindControl("txtStudentDOB") as TextBox;
   if(txtStudentDOB != null)
   {
      txtStudentDOB.Text = Calendar1.SelectedDate.ToShortDateString();
      Calendar1.Visible = false;
   }
}