伙计们，我有一个表格，我正在使用 2 UpdatePanels。当我尝试使用 html 输入文件控件上传文件时遇到问题，它是上传空值。我的 html 输入类型文件控件位于第一个更新面板中。提前谢谢任何帮助....
<%@ Page Title="InstructorView" Language="C#" MasterPageFile="~/AdminDashboard.Master"
AutoEventWireup="true" CodeFile="InstructorView.aspx.cs" Inherits="Admin_InstructorView" %>
<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="ajax" %>
<asp:Content ID="Content1" ContentPlaceHolderID="HeadContent" runat="Server">
<link rel="shortcut icon" href="../App_Themes/Admintheme/images/LIT_Icon.ico" />
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="Server">
<script language="javascript" type="text/javascript">
function ConfirmDelete() {
return confirm("Are u sure u want to delete this records?")
}
</script>
<ajax:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server">
</ajax:ToolkitScriptManager>
<asp:UpdatePanel ID="UpdatePanel1" UpdateMode="Conditional" ChildrenAsTriggers="true" runat="server">
<ContentTemplate >
<div class="grid_16" id="content">
<div class="grid_9">
<h1 class="instructorprofile">
Instructors Status</h1>
<div class="portlet-content">
<asp:GridView ID="grdInst" runat="server" AutoGenerateColumns="false" CellPadding="4"
Width="900px" OnRowDeleting="grdInst_RowViewing" AllowPaging="true" PageSize="10"
CssClass="box-table-a">
<%-- OnPageIndexChanging="grdInst_PageIndexChanging"--%>
<FooterStyle />
<Columns>
<asp:BoundField DataField="InstructorID" HeaderText="Instructor Code" ReadOnly="true"
ItemStyle-HorizontalAlign="Center" ItemStyle-Width="90px" />
<asp:BoundField DataField="FirstName" HeaderText="First Name" />
<asp:BoundField DataField="LastName" HeaderText="Last Name" />
<asp:BoundField DataField="IsActive" HeaderText="Status" />
<asp:TemplateField ItemStyle-Width="30px" HeaderText="View" ItemStyle-HorizontalAlign="Center">
<ItemTemplate>
<asp:LinkButton ID="lkView" runat="server" CommandName="Delete" Text="" CssClass="view_icon"
ToolTip="Click for View" />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField ItemStyle-Width="30px" HeaderText="Edit" ItemStyle-HorizontalAlign="Center">
<ItemTemplate>
<asp:LinkButton ID="lnkEdit" runat="server" Text="" CssClass="edit_icon" ToolTip="Click for Edit"
OnClick="Edit"></asp:LinkButton>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField ItemStyle-Width="30px" HeaderText="" ItemStyle-HorizontalAlign="Center">
<ItemTemplate>
<asp:LinkButton ID="lkDelete" runat="server" CssClass="delete_icon" ToolTip="Click for Delete"
OnClientClick='return confirm ("Are you sure you want to delete this entry?");'
CommandName="Delete" OnClick="Delete" Text="" Visible="false" />
</ItemTemplate>
</asp:TemplateField>
</Columns>
<RowStyle />
<EditRowStyle />
<SelectedRowStyle />
<PagerStyle HorizontalAlign="Center" />
<HeaderStyle />
<AlternatingRowStyle />
</asp:GridView>
</div>
<asp:Panel ID="pnlInst" runat="server" Visible="false" Height="512px">
<div class="grid_16" id="content_popup" style="margin: 0px auto; display: block;
float: none;">
<span style="display: block; float: right; margin-right: 0; margin-top: -10px;">
<asp:ImageButton ID="ImageButton2" ImageUrl="../AppImages/close-popup.png" runat="server" />
</span>
<h1 class="instructorprofile">
Instructor Details</h1>
<div class="portlet-content"
style="overflow: auto; height: 400px; width: 370px;">
<label>
<asp:Label ID="Label20" runat="server" Text="Course I will be Teaching"></asp:Label></label>
<asp:DropDownList ID="drpCourseName" runat="server" CssClass="smallInput" AutoPostBack="true">
</asp:DropDownList>
<asp:TextBox ID="txtSpecialization" runat="server" Visible="false" CssClass="smallInput"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator9" runat="server" ControlToValidate="drpCourseName"
ErrorMessage="" ValidationGroup="1" Display="Dynamic">
<div class="error"> <p class="info">
<span class="info_inner">Course Name is Required!</span></p></div>
</asp:RequiredFieldValidator>
<label>
<asp:Label ID="Label1" runat="server" Text="First Name"></asp:Label>
</label>
<asp:TextBox ID="txtFirstName" runat="server" CssClass="smallInput"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator7" runat="server" ControlToValidate="txtFirstName"
ErrorMessage="" ValidationGroup="1" Display="Dynamic">
<div class="error"> <p class="info">
<span class="info_inner">First Name is Required!</span></p></div>
</asp:RequiredFieldValidator>
<label>
<asp:Label ID="Label2" runat="server" Text="Last Name"></asp:Label>
</label>
<asp:TextBox ID="txtLastName" CssClass="smallInput" runat="server"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator8" runat="server" ControlToValidate="txtLastName"
ErrorMessage="" ValidationGroup="1" Display="Dynamic">
<div class="error"> <p class="info">
<span class="info_inner">Last Name is Required!</span></p></div>
</asp:RequiredFieldValidator>
<label>
<asp:Label ID="Label10" runat="server" Text="Cell Number"></asp:Label></label>
<asp:TextBox ID="txtCellNumber1" CssClass="smallInput" runat="server"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator13" runat="server" ControlToValidate="txtCellNumber1"
ErrorMessage="" ValidationGroup="1" Display="Dynamic">
<div class="error"> <p class="info">
<span class="info_inner">Cell Number is Required! </span></p></div>
</asp:RequiredFieldValidator>
<asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" ControlToValidate="txtCellNumber1"
ErrorMessage="" ValidationExpression="^[0-9]*$" Display="Dynamic" ValidationGroup="1">
<div class="error"> <p class="info">
<span class="info_inner"> Invalid Format</span></p></div>
</asp:RegularExpressionValidator>
<label>
<asp:Label ID="Label21" runat="server" Text="Email"></asp:Label></label>
<asp:TextBox ID="txtEmail" CssClass="smallInput" runat="server"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator14" runat="server" ControlToValidate="txtEmail"
ErrorMessage="" ValidationGroup="1" Display="Dynamic">
<div class="error"> <p class="info">
<span class="info_inner">Email is Required! </span></p></div>
</asp:RequiredFieldValidator>
<asp:RegularExpressionValidator ID="ValidateEmailAddress" ErrorMessage="Enter Valid Email ID"
ControlToValidate="txtEmail" runat="server" Display="Dynamic" ValidationExpression="\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*">
<div class="error"> <p class="info">
<span class="info_inner">Enter Valid Email Id! </span></p></div>
</asp:RegularExpressionValidator>
<label>
Upload Contract</label>
<input id="inputContract" type="file" runat="server" />
<asp:UpdatePanel ID="UpdatePanel2" UpdateMode="Conditional" ChildrenAsTriggers ="true" runat="server" >
<ContentTemplate>
<asp:Button ID="btnUpload" runat="server" CssClass="black_button" Text="Upload File"
OnClick="btnUpload_Click" CausesValidation="false" />
<asp:Label ID="lblContract" runat="server" Text="" Visible="true"></asp:Label>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="btnUpload" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
<asp:UpdateProgress ID="UpdateProgress1" AssociatedUpdatePanelID ="UpdatePanel1" runat="server">
<ProgressTemplate>
Please Wait while We Save Your Changes....<img alt="" src="../AppImages/ajax-loader-7.gif" />
</ProgressTemplate>
</asp:UpdateProgress> <label>
<asp:Label ID="Label7" runat="server" Text="Current Status"></asp:Label>
</label>
<asp:RadioButtonList ID="rbtnIsActive" runat="server" RepeatDirection="horizontal">
<asp:ListItem Value="True">Active </asp:ListItem>
<asp:ListItem Selected="True" Value="False">Blocked </asp:ListItem>
</asp:RadioButtonList>
<asp:Button ID="btnSave" runat="server" Text="Save" CssClass="black_button"
ValidationGroup="1" onclick="btnSave_Click"
/>
<asp:Button ID="btnCancel" runat="server" CssClass="black_button" Text="Cancel" OnClientClick="return Hidepopup()" />
<asp:Label ID="lblUserName" runat="server" Visible="false"></asp:Label>
<asp:Label ID="lblPassWord" runat="server" Visible="false"></asp:Label>
</div>
</div>
</asp:Panel>
<asp:LinkButton ID="lnkFake" runat="server"></asp:LinkButton>
<ajaxToolkit:ModalPopupExtender ID="popup" runat="server" DropShadow="false" PopupControlID="pnlInst"
TargetControlID="lnkFake" >
</ajaxToolkit:ModalPopupExtender>
</div>
</div>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="btnSave" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
</asp:Content>