中繼器內的dropdownlist的設置值

Question

我有一個內置dropdownlist的中繼器。中繼器外還有另一個單獨的下拉列表。用戶將在這個ddl中選擇一個值，點擊一個按鈕，並且所選擇的值將被填充在中繼器內的所有ddl中，這些ddl是空白的。注意：ddl的文本爲selectedvalue（而不是ints）。

不幸的是我的代碼不起作用。

我的標記：

<asp:Repeater ID="AttendanceRepeater" runat="server" DataSourceID="AttendanceSqlDataSource" OnItemDataBound="AttendanceRepeater_ItemDataBound"> 
 
       <ItemTemplate> 
 
        <br /> 
 
        <table> 
 
         <tr> 
 
          <td style="width: 50px"></td> 
 
          <td style="width: 300px"> 
 
           <asp:Label ID="StudentNameLabel" runat="server" Text='<%# Eval("STUDENT_NAME") %>'></asp:Label> 
 
          </td> 
 
          <td style="width: 200px"> 
 
           <asp:DropDownList ID="AttendStatusDropDownList" runat="server" 
 
            SelectedValue='<%# Eval("ATTENDANCE_STATUS") %>'> 
 
            <asp:ListItem Value="" Text=""></asp:ListItem> 
 
            <asp:ListItem Value="ABSENTE" Text="Absent Excused"></asp:ListItem> 
 
            <asp:ListItem Value="ABSENTU" Text="Absent Unexcused"></asp:ListItem> 
 
            <asp:ListItem Value="CIN" Text="Chk In No (Absent)"></asp:ListItem> 
 
            <asp:ListItem Value="CIY" Text="Chk In Yes (Present)"></asp:ListItem> 
 
            <asp:ListItem Value="NR" Text="Attend Not Reqd"></asp:ListItem> 
 
            <asp:ListItem Value="PRESENT" Text="Present"></asp:ListItem> 
 
            <asp:ListItem Value="TM005" Text="Time Missed 005 Min"></asp:ListItem> 
 
            <asp:ListItem Value="TM010" Text="Time Missed 010 Min"></asp:ListItem> 
 
            <asp:ListItem Value="TM015" Text="Time Missed 015 Min"></asp:ListItem> 
 
            <asp:ListItem Value="TM030" Text="Time Missed 030 Min"></asp:ListItem> 
 
            <asp:ListItem Value="TM045" Text="Time Missed 045 Min"></asp:ListItem> 
 
            <asp:ListItem Value="TM060" Text="Time Missed 1hr"></asp:ListItem> 
 
            <asp:ListItem Value="TM075" Text="Time Missed 1hr 15mi"></asp:ListItem> 
 
            <asp:ListItem Value="TM090" Text="Time Missed 1hr 30mi"></asp:ListItem> 
 
            <asp:ListItem Value="TM105" Text="Time Missed 1hr 45mi"></asp:ListItem> 
 
            <asp:ListItem Value="TM120" Text="Time Missed 2hr"></asp:ListItem> 
 
            <asp:ListItem Value="TM135" Text="Time Missed 2hr 15mi"></asp:ListItem> 
 
            <asp:ListItem Value="TM150" Text="Time Missed 2hr 30mi"></asp:ListItem> 
 
            <asp:ListItem Value="TM165" Text="Time Missed 2hr 45mi"></asp:ListItem> 
 
            <asp:ListItem Value="TM180" Text="Time Missed 3hr"></asp:ListItem> 
 
            <asp:ListItem Value="TM195" Text="Time Missed 3hr 15mi"></asp:ListItem> 
 
            <asp:ListItem Value="TM210" Text="Time Missed 3hr 30mi"></asp:ListItem> 
 
            <asp:ListItem Value="TM225" Text="Time Missed 3hr 45mi"></asp:ListItem> 
 
            <asp:ListItem Value="TM240" Text="Time Missed 4hr"></asp:ListItem> 
 
            <asp:ListItem Value="TM255" Text="Time Missed 4hr 15mi"></asp:ListItem> 
 
            <asp:ListItem Value="TM310" Text="Time Missed 4hr 30mi"></asp:ListItem> 
 
            <asp:ListItem Value="TM325" Text="Time Missed 4hr 45mi"></asp:ListItem> 
 
            <asp:ListItem Value="WD" Text="Withdrawn"></asp:ListItem> 
 
           </asp:DropDownList> 
 
           <asp:RequiredFieldValidator ID="AttendStatusValidator" runat="server" 
 
            ErrorMessage="Required field" ControlToValidate="AttendStatusDropDownList"> 
 
           </asp:RequiredFieldValidator> 
 
          </td> 
 
          <td style="width: 200px"> 
 
           <asp:TextBox ID="CommentsTextBox" runat="server" TextMode="MultiLine" 
 
            Text='<%# Eval("COMMENTS") %>'></asp:TextBox> 
 
          </td> 
 
          <td> 
 
<%--        <asp:CheckBox ID="ChangeCheckBox" runat="server" Visible="true" />--%> 
 
           <asp:Label ID="PeopleCodeIdLabel" runat="server" Visible="false" Text='<%# Eval("PEOPLE_CODE_ID") %>'></asp:Label> 
 
           <asp:Label ID="AcademicYearLabel" runat="server" Visible="false" Text='<%# Eval("ACADEMIC_YEAR") %>'></asp:Label> 
 
           <asp:Label ID="AcademicTermLabel" runat="server" Visible="false" Text='<%# Eval("ACADEMIC_TERM") %>'></asp:Label> 
 
           <asp:Label ID="AcademicSessionLabel" runat="server" Visible="false" Text='<%# Eval("ACADEMIC_SESSION") %>'></asp:Label> 
 
           <asp:Label ID="EventIdLabel" runat="server" Visible="false" Text='<%# Eval("EVENT_ID") %>'></asp:Label> 
 
           <asp:Label ID="EventSubTypeLabel" runat="server" Visible="false" Text='<%# Eval("EVENT_SUB_TYPE") %>'></asp:Label> 
 
           <asp:Label ID="SectionLabel" runat="server" Visible="false" Text='<%# Eval("SECTION") %>'></asp:Label> 
 
           <asp:Label ID="TranAttendanceIdLabel" runat="server" Visible="false" Text='<%# Eval("TranAttendanceId") %>'></asp:Label> 
 
          </td> 
 
         </tr> 
 
        </table> 
 
        <br /> 
 
       </ItemTemplate> 
 
      </asp:Repeater>

代碼按鈕（注意下拉列表的AttendanceStatusdropdownlist和AttendStatusAllDropDownList命名。）

protected void ApplyToAllButton_Click(object sender, EventArgs e) 
{ 
    string defaultStatus = AttendStatusAllDropDownList.SelectedValue; 

    foreach (RepeaterItem item in AttendanceRepeater.Items) 
    { 
     DropDownList ddl = (DropDownList)item.FindControl("AttendanceStatusDropDownList"); 
     if (string.IsNullOrWhiteSpace(ddl.SelectedValue)) 
     { 
      //set the ddl to the value selected from the other ddl 
      ddl.SelectedValue = defaultStatus; 

     } 
    } 
    //Save changes to all 
    SaveButton_Click(null, null); 
} 

的值不在中繼器內部的下拉菜單中填充。我搜索谷歌，但無法找到任何具體的東西，我試圖。任何幫助將非常感激。

在此先感謝。 皮特

Answer 1

。在你的FindControl值和差異直放站內的DropDownList的ID。

中繼器：AttendStatusDropDownList

的FindControl：AttendanceStatusDropDownList

請參見下面的更新代碼段。

protected void ApplyToAllButton_Click(object sender, EventArgs e) 
{ 
    foreach (RepeaterItem item in AttendanceRepeater.Items) 
    { 
     DropDownList ddl = (DropDownList)item.FindControl("AttendStatusDropDownList"); 

     if (ddl != null && string.IsNullOrEmpty(ddl.SelectedValue)) 
     { 
      ddl.SelectedValue = AttendStatusAllDropDownList.SelectedValue; 
     } 
    }  
} 

ASPX頁面

<asp:DropDownList ID="AttendStatusAllDropDownList" runat="server"> 
    <asp:ListItem Value="" Text=""></asp:ListItem> 
    <asp:ListItem Value="TM005" Text="Time Missed 005 Min"></asp:ListItem> 
    <asp:ListItem Value="TM010" Text="Time Missed 010 Min"></asp:ListItem> 
    <asp:ListItem Value="TM015" Text="Time Missed 015 Min"></asp:ListItem> 
    <asp:ListItem Value="TM030" Text="Time Missed 030 Min"></asp:ListItem> 
    <asp:ListItem Value="TM045" Text="Time Missed 045 Min"></asp:ListItem> 
</asp:DropDownList> 
<br /> 
<asp:Button ID="Button1" runat="server" Text="Button" OnClick="ApplyToAllButton_Click" CausesValidation="false" /> 
<br /> 
<br /> 
<asp:Repeater ID="AttendanceRepeater" runat="server"> 
    <ItemTemplate> 
     <asp:DropDownList ID="AttendStatusDropDownList" runat="server"> 
      <asp:ListItem Value="" Text=""></asp:ListItem> 
      <asp:ListItem Value="TM005" Text="Time Missed 005 Min"></asp:ListItem> 
      <asp:ListItem Value="TM010" Text="Time Missed 010 Min"></asp:ListItem> 
      <asp:ListItem Value="TM015" Text="Time Missed 015 Min"></asp:ListItem> 
      <asp:ListItem Value="TM030" Text="Time Missed 030 Min"></asp:ListItem> 
      <asp:ListItem Value="TM045" Text="Time Missed 045 Min"></asp:ListItem> 
     </asp:DropDownList><br /> 
    </ItemTemplate> 
</asp:Repeater>