我已经成功完成了一个组织的网络应用程序，它符合预期，但我注意到一个问题，并尝试通过在谷歌搜索并询问老年人来治愈它，但这些都没有帮助。
问题：我在页面上有多个下拉列表，其中在一个下拉列表中选择值会触发另一个下拉列表的加载，即Country＆gt;城市的情况，问题是，每当我点击任何值，它滚动页面到顶部，我必须再次滚动回来然后一次又一次，这看起来很糟糕和不专业。请帮帮我。
代码：
<%@ Page Title="" Language="C#" MasterPageFile="~/MasterPage.master" MaintainScrollPositionOnPostback="true" AutoEventWireup="true" CodeFile="frmReceivedSms.aspx.cs" Inherits="SmsComplaints" %>
<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="asp" %>
<%@ Register assembly="Microsoft.ReportViewer.WebForms,Version=11.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91" namespace="Microsoft.Reporting.WebForms" tagprefix="rsweb" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" Runat="Server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server">
<script type="text/javascript">
$(document).ready(function () {
$("#btnSendSms").hide();
$("#btnDelete").hide();
$("#btnCancel").hide();
$("#lblSelectedID-Span").hide();
$("#txtSelectedID-Span").hide();
var showHide = $("#HiddenFieldShowHideButtons").val();
if (showHide == "True") {
$("#btnSendSms").show();
$("#btnDelete").show();
$("#btnCancel").show();
$("#lblSelectedID-Span").show();
$("#txtSelectedID-Span").show();
$("#buttonSearch").hide();
$("#Save-Span").hide();
$("#HiddenFieldShowHideButtons").val("False");
}
$("#btnSendSms").click(function () {
$("#ConfirmMsg").text("Are you sure to update this record?");
$("#Delete-Span").hide();
$("#lblSelectedID-Span").hide();
$("#txtSelectedID-Span").hide();
$("#Save-Span").show();
$("#buttonSearch").show();
$("#Update-Span").show();
$("#btnSendSms").hide();
$("#btnDelete").hide();
$("#btnCancel").hide();
$("#ModalConfirmAction").modal({ show: true })
});
$("#btnDelete").click(function () {
$("#ConfirmMsg").text("Are you sure to delete this record?");
$("#Update-Span").hide();
$("#lblSelectedID-Span").hide();
$("#txtSelectedID-Span").hide();
$("#Delete-Span").show();
$("#Save-Span").show();
$("#buttonSearch").show();
$("#btnDelete").hide();
$("#btnSendSms").hide();
$("#btnCancel").hide();
$("#ModalConfirmAction").modal({ show: true })
});
$("#btnCancel").click(function () {
$("#btnSendSms").hide();
$("#btnDelete").hide();
$("#btnCancel").hide();
$("#lblSelectedID-Span").hide();
$("#txtSelectedID-Span").hide();
$("#buttonSearch").show();
$("#Save-Span").show();
ClearTextBoxes();
});
});
function ClearTextBoxes() {
$("input[type=text]").each(function () {
$(this).val("");
});
}
function validate() {
var setValue = false;
var NotificationSummary = new Array();
var fields = new Array("Admin Role");
var txtboxes = new Array($("#txtAdminName"));
$(txtboxes).each(function (index) {
if ($(this).val() == "") {
NotificationSummary[index] = fields[index];
setValue = true;
}
});
if (setValue == true) {
$("#ConfirmMsg").text = NotificationSummary.join(",");
$("#ModalConfirmAction").modal({ show: true })
}
return setValue;
}
$("#Save-Span").click(function () {
validate();
});
</script>
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<%--<script type="text/javascript"> //Maintain scroll on post back but doesn't load values in relevant drop down
var xPos, yPos;
var prm = Sys.WebForms.PageRequestManager.getInstance();
prm.add_beginRequest(BeginRequestHandler);
prm.add_endRequest(EndRequestHandler);
function BeginRequestHandler(sender, args) {
xPos = $get('ContentPlaceHolder1').scrollLeft;
yPos = $get('ContentPlaceHolder1').scrollTop;
}
function EndRequestHandler(sender, args) {
$get('ContentPlaceHolder1').scrollLeft = xPos;
$get('ContentPlaceHolder1').scrollTop = yPos;
}
</script>--%>
<div class="widget">
<div class="widget-header">
<div class="title">
Received Complaints Via Sms
</div>
<!-- widget title-->
</div> <!-- widget header -->
<div class="widget-body">
<div class="row-fluid">
<!-- cons start -->
<div class="shortcut-group">
<asp:HiddenField ID="HiddenFieldSetMessage" runat="server"
ClientIDMode="Static"/>
<asp:HiddenField ID="HiddenFieldShowMessage" runat="server"
ClientIDMode="Static"/>
<asp:HiddenField ID="HiddenFieldIsValidDropDownValue" runat="server"
ClientIDMode="Static" />
<asp:UpdatePanel ID="updGridViewSMS" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<label><b>Search By Date Range</b></label>
<asp:Label ID="lblDateFrom" runat="server" Text="From"></asp:Label>
<asp:TextBox ID="txtFromDate" runat="server" ></asp:TextBox>
<asp:CalendarExtender ID="CalendarExtenderFromDate" Format="dd/MMM/yyyy" TargetControlID="txtFromDate" runat="server">
</asp:CalendarExtender>
<asp:RequiredFieldValidator ID="RequiredFieldValidator9" runat="server"
ControlToValidate="txtFromDate" Display="None" ErrorMessage=""
ForeColor="Red" >
</asp:RequiredFieldValidator>
<asp:Label ID="lblDateTo" runat="server" Text="To"></asp:Label>
<asp:TextBox ID="txtToDate" runat="server"></asp:TextBox>
<asp:CalendarExtender ID="CalendarExtenderToDate" Format="dd/MMM/yyyy" TargetControlID="txtToDate" runat="server">
</asp:CalendarExtender>
<asp:RequiredFieldValidator ID="RequiredFieldValidator10" runat="server"
ControlToValidate="txtToDate" Display="None" ErrorMessage=""
ForeColor="Red" >
</asp:RequiredFieldValidator>
<asp:Button ID="btnSearchByDate" CssClass="btn btn-success" runat="server" Text="Search"
ClientIDMode="Static" OnClick="btnSearchByDate_Click" />
<asp:ValidationSummary
HeaderText="Requires Date Range:"
DisplayMode="SingleParagraph"
EnableClientScript="true"
ForeColor="Red"
runat="server" ID="ValidationSummary1"/>
<label runat="server" id="lblSelectionMessage" style="color:navy; font-size:12px; font-style:italic" visible="false">
Please select one validity dropdown at a time
</label>
<asp:GridView ID="GridViewSmsComplaints" AllowPaging="True" PageSize="5" runat="server" AutoGenerateColumns="False" CssClass="mGrid" BorderColor="#333333" Width="650px" OnRowDataBound="GridViewSmsComplaints_RowDataBound" OnPageIndexChanging="GridViewSmsComplaints_PageIndexChanging" >
<Columns>
<asp:BoundField HeaderText="Sms ID" DataField="ID" />
<asp:BoundField HeaderText="Recieving Date" DataField="RecievingDate" />
<%--<asp:BoundField HeaderText="ToMobileNo" DataField="ToMobileNo" /> --%>
<asp:BoundField HeaderText="Complainant Mob No." DataField="FromMobileNo" />
<asp:BoundField HeaderText="Complaint" DataField="Message" >
<ItemStyle Wrap="True" />
</asp:BoundField>
<asp:TemplateField HeaderText="Complete/InComplete">
<ItemTemplate>
<%--<asp:CheckBox ID="ckboxIsComplaint" runat="server" />--%>
<asp:DropDownList ID="ddlIsComplaint" runat="server" AutoPostBack="true" OnSelectedIndexChanged="ddlIsComplaint_SelectedIndexChanged">
<asp:ListItem Text="-Select-" Value="-1"></asp:ListItem>
<asp:ListItem Text="InComplete" Value="0"></asp:ListItem>
<asp:ListItem Text="Complete" Value="1"></asp:ListItem>
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<br />
<asp:Panel ID="pnlBoxesDropDowns" runat="server">
<label>Complainant</label>
<asp:TextBox ID="txtComplainant" runat="server" CssClass="textField_width"></asp:TextBox>
<asp:RequiredFieldValidator ID="ReqFieldValdiatorComplainant" runat="server" ControlToValidate="txtComplainant" ErrorMessage="Complainant is Required" ForeColor="Red" SetFocusOnError="True" ValidationGroup="Complaints">Complainant is Required
</asp:RequiredFieldValidator>
<label style="width:400px">Relevant Region</label>
<asp:DropDownList ID="ddlRegions" runat="server" CssClass="DropDown_Width" Width="147px" OnSelectedIndexChanged="ddlRegions_SelectedIndexChanged" AppendDataBoundItems="True" AutoPostBack="true" >
<asp:ListItem Value="-1" Selected="True">-Select-</asp:ListItem>
</asp:DropDownList>
<asp:RequiredFieldValidator ID="ReqFieldValidatorRegions" runat="server"
ControlToValidate="ddlRegions" ErrorMessage="Region is Required" InitialValue="-1"
ForeColor="Red" ValidationGroup="Complaints">Region is Required</asp:RequiredFieldValidator>
<label style="width:400px">Relevant District</label>
<asp:DropDownList ID="ddlDistricts" runat="server" CssClass="DropDown_Width" Width="147px" OnSelectedIndexChanged="ddlDistricts_SelectedIndexChanged" AutoPostBack="true">
</asp:DropDownList>
<asp:RequiredFieldValidator ID="ReqFieldValidatorDistricts" runat="server"
ControlToValidate="ddlDistricts" ErrorMessage="Region is Required" InitialValue="-1"
ForeColor="Red" ValidationGroup="Complaints">District is Required</asp:RequiredFieldValidator>
<label>Relevant P.Station</label>
<asp:DropDownList ID="ddlPoliceStations" runat="server" Width="147px" CssClass="DropDown_Width">
</asp:DropDownList>
<asp:RequiredFieldValidator ID="ReqFieldValidatorPoliceStations" runat="server"
ControlToValidate="ddlPoliceStations" ErrorMessage="Police Station is Required" InitialValue="-1"
ForeColor="Red" ValidationGroup="Complaints">Police Station is Required</asp:RequiredFieldValidator>
<label>Priority</label>
<asp:DropDownList ID="ddlPriority" runat="server">
<asp:ListItem Text="Top" Value="1"></asp:ListItem>
<asp:ListItem Text="Normal" Value="2"></asp:ListItem>
</asp:DropDownList>
</asp:Panel>
<br />
<br />
<asp:Timer runat="server" Interval="60000" ID="RefreshSmsComplaints" OnTick="RefreshSmsComplaints_Tick" />
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="RefreshSmsComplaints" EventName="Tick" />
</Triggers>
</asp:UpdatePanel>
<asp:Button ID="btnSendSms" ValidationGroup="Complaints" runat="server" CssClass="btn btn-success"
OnClick="btnSendSms_Click" Text="Send Sms" />
<%--<asp:Button ID="btnGenerateReport" CssClass="btn btn-success" runat="server" Text="Generate Report"
ClientIDMode="Static" OnClick="btnGenerateReport_Click" />--%>
<br />
<br />
<rsweb:ReportViewer ID="ReportViewer1" runat="server" Font-Names="Verdana" Font-Size="8pt" WaitMessageFont-Names="Verdana" WaitMessageFont-Size="14pt" Width="550px">
<LocalReport ReportPath="Reports\GetReceivedComplaintsReport.rdlc">
</LocalReport>
</rsweb:ReportViewer>
<br />
<br />
 
</div> <!-- shourtcut group">
<!-- cons end -->
</div> <!-- row fluid -->
</div> <!-- widget body-->
</div> <!-- widget-->
<div class="clearfix"></div>
<!-- Modal -->
</asp:Content>
即使我在页面指令和代码中使用了maintaincrollbackposition属性，但它不起作用，我使用的是firefox。即使我在scriptmanager标签之后使用了这段代码，但它的工作方式并不完全像是保持向后滚动页面位置，但在点击时不会加载值。
<script type="text/javascript">
var xPos, yPos;
var prm = Sys.WebForms.PageRequestManager.getInstance();
prm.add_beginRequest(BeginRequestHandler);
prm.add_endRequest(EndRequestHandler);
function BeginRequestHandler(sender, args) {
xPos = $get('scrollDiv').scrollLeft;
yPos = $get('scrollDiv').scrollTop;
}
function EndRequestHandler(sender, args) {
$get('scrollDiv').scrollLeft = xPos;
$get('scrollDiv').scrollTop = yPos;
}
</script>
答案 0 :(得分：0)
作为替代方案，您可以在第一个Dropdownlist选择中使用Focus（）方法，
考虑这是一个例子
代码背后
Protected void ddlstate_click(object sender, Eventargs e)
{
ddlcity.Focus();
}
它会按你的意愿行事。