C# 下拉列表选定索引已更改未触发
本文关键字：下拉列表 索引 | 更新日期: 2023-09-27 18:34:28
从代码隐藏更新UpdatePanel后，Dropdownlist_OnSelectedIndexChanged和Checkbox_OnCheckedChanged事件都没有从UpdatePanel内触发的问题。
从下面的代码中可以看出，客户端的DropDownList和CheckBoxes绑定，以及加载/重新加载时，所有Controls绑定到数据库中的值。
当页面最初加载一些数据时，Dropdownlist_OnSelectedIndexChanged和Checkbox_OnCheckedChanged事件都会按预期触发。它们还通过代码隐藏更新数据库值。
但是，例如，如果我更改GridView数据的数据范围，从而刷新UpdatePanel并重新绑定所有数据，则Dropdownlist_OnSelectedIndexChanged和Checkbox_OnCheckedChanged事件将停止触发。
我试图通过在 Dropdownlist_OnSelectedIndexChanged 和 Checkbox_OnCheckedChanged 事件应该调用相关函数时向代码添加各种断点来诊断这一点，但从未到达断点。
我还在上述Controls所在的GridView中启用了OnSelectedIndexChanged，并且每次都按预期触发......即使上述Controls没有。
我的代码是：
<%@ Page Title="Downtime" Language="C#"
MasterPageFile="~/Reporting/Reporting.Master" AutoEventWireup="true" CodeBehind="GensetDowntime.aspx.cs" Inherits="ReportingSystemV2.Reporting.GensetDowntime" %>
<%@ MasterType VirtualPath="~/Reporting/Reporting.Master" %>
<asp:Content ID="Content1" ContentPlaceHolderID="ReportingSubContent" runat="server">
<div class="container-fluid">
<asp:UpdatePanel ID="updPanelDowntime" runat="server">
<ContentTemplate>
<%--Summary Table--%>
<div id="DowntimeSummaryDiv" visible="false" runat="server">
<table id="DowntimeSummary" class="table table-striped table-condensed" align="center" style="width: 50%">
<thead>
<tr>
<th>Gross Hours</th>
<th>Run Hours</th>
<th>Total Exempts</th>
<th>Total Non-Exempts</th>
<th>Difference</th>
</tr>
</thead>
<tbody>
<tr>
<td>
<asp:Label ID="lblSumGrossHrs" runat="server" ToolTip="Total hours in this period"></asp:Label></td>
<td>
<asp:Label ID="lblSumRunHours" runat="server" ToolTip="Engine running hours in this period"></asp:Label></td>
<td>
<asp:Label ID="lblSumTotExempts" runat="server" ToolTip="(hhhh:mm)"></asp:Label></td>
<td>
<asp:Label ID="lblSumTotNonExempts" runat="server" ToolTip="(hhhh:mm)"></asp:Label></td>
<td>
<asp:Label ID="lblSumDifference" runat="server" ToolTip="Difference (Minutes) = Gross Hours - (Run Hours + Total Exempt + Total Non-Exempt)"></asp:Label></td>
</tr>
</tbody>
</table>
</div>
<%--End of Summary Table--%>
<%--Downtime Table--%>
<div class="row">
<div id="downtimeDiv" runat="server">
<asp:GridView ID="gridDowntime" runat="server" AutoGenerateColumns="False" GridLines="None" CssClass="table table-striped table-condensed"
OnRowDataBound="gridDowntime_RowDataBound"
OnSelectedIndexChanged="gridDowntime_SelectedIndexChanged"
DataKeyNames="ID,ID_Location,iddown,idup,dtdown,dtup,isexempt" EmptyDataText="No exempts in the selected period.">
<Columns>
<asp:TemplateField>
<ItemTemplate>
<%# Container.DataItemIndex + 1 %>
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="ID" />
<asp:BoundField DataField="dtdown" DataFormatString="{0:dd/MM/yyyy HH:mm:ss.fff}"
HeaderText="Down" />
<asp:BoundField DataField="dtup" DataFormatString="{0:dd/MM/yyyy HH:mm:ss.fff}"
HeaderText="Up" />
<asp:BoundField DataField="timedifference"
HeaderText="Duration (min)" DataFormatString="{0:D4}" />
<asp:BoundField DataField="REASON"
HeaderText="Reason" />
<asp:TemplateField HeaderText="Exempt?">
<ItemTemplate>
<asp:DropDownList ID="ddlDowntimeExempt" AutoPostBack="true" runat="server"
OnSelectedIndexChanged="ddlDowntimeExempt_SelectedIndexChanged">
<asp:ListItem Value="-1">Unverified</asp:ListItem>
<asp:ListItem Value="1">Yes</asp:ListItem>
<asp:ListItem Value="0">No</asp:ListItem>
</asp:DropDownList>
<asp:Label ID="lblDowntimeExempt" runat="server" Text='<%#DataBinder.Eval(Container.DataItem,"isexempt")%>' Visible="false"></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Exclude?">
<ItemTemplate>
<asp:CheckBox ID="chkDowntimeExclude" runat="server" Checked='<%#Convert.ToBoolean(Eval("ISEXCLUDED")) %>' OnCheckedChanged="chkDowntimeExclude_CheckedChanged" AutoPostBack="true"/>
</ItemTemplate>
</asp:TemplateField>
<asp:CommandField ShowSelectButton="True" SelectText="Details" />
</Columns>
</asp:GridView>
</div>
</div>
<%--End of Downtime Table--%>
<%--Shutdown Values--%>
<div id="downtimeValueDiv" runat="server">
<asp:GridView ID="gridDowntimeRecalc" runat="server" AutoGenerateColumns="False" GridLines="None"
CssClass="table table-striped table-condensed" Width="50%" HorizontalAlign="Center">
<Columns>
<asp:BoundField DataField="dtdown" DataFormatString="{0:dd/MM/yyyy HH:mm:ss.fff}"
HeaderText="Downtime" />
<asp:BoundField DataField="dtup" DataFormatString="{0:dd/MM/yyyy HH:mm:ss.fff}"
HeaderText="Uptime" />
<asp:BoundField DataField="TimeDifference"
HeaderText="Duration (min)" DataFormatString="{0:D4}" />
<asp:TemplateField ShowHeader="false">
<ItemTemplate>
<asp:LinkButton ID="lnkReset" runat="server" OnClick="lnkReset_Click" ToolTip="Reset">
<span aria-hidden="true" class="fa fa-rotate-left"></span>
</asp:LinkButton>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<div class="span7 text-center">
<br />
<div class="pull-right">
<div class="form-inline">
Events (min +/-):
<asp:DropDownList ID="ddlAdjust" runat="server" CssClass="form-control input-sm"
OnSelectedIndexChanged="ddlAdjust_SelectedIndexChanged" AutoPostBack="True">
<asp:ListItem>0</asp:ListItem>
<asp:ListItem>5</asp:ListItem>
<asp:ListItem Selected="True">10</asp:ListItem>
<asp:ListItem>15</asp:ListItem>
<asp:ListItem>30</asp:ListItem>
<asp:ListItem>45</asp:ListItem>
<asp:ListItem>60</asp:ListItem>
<asp:ListItem>90</asp:ListItem>
<asp:ListItem>120</asp:ListItem>
<asp:ListItem>240</asp:ListItem>
</asp:DropDownList>
</div>
</div>
<br />
</div>
</div>
<%--End of Shutdown Values--%>
<%--Details Row--%>
<div id="detailDiv" runat="server">
<asp:GridView ID="gridDowntimeDetail" runat="server" AutoGenerateColumns="False"
GridLines="None" CssClass="table table-condensed"
OnRowDataBound="gridDowntimeDetail_RowDataBound"
OnRowCommand="gridDowntimeDetail_RowCommand"
DataKeyNames="ExemptId">
<Columns>
<asp:TemplateField>
<HeaderTemplate>
<asp:LinkButton ID="lnkBack" runat="server" Text="Back" CommandName="Back"
CommandArgument="<% Container.DataItemIndex + 1 %>"
CausesValidation="false">
<span aria-hidden="true" class="fa fa-arrow-circle-left"></span>
</asp:LinkButton>
</HeaderTemplate>
<ItemTemplate>
<%# Container.DataItemIndex + 1 %>
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="Timestamp" DataFormatString="{0:dd/MM/yyyy HH:mm:ss.fff}" HeaderText="Time Stamp" />
<asp:BoundField DataField="Reason" HeaderText="Reason" />
<asp:BoundField DataField="Event" HeaderText="Event" />
</Columns>
</asp:GridView>
<br />
<br />
</div>
<%--End of Details Row--%>
<%--Notes Row--%>
<div class="span7 text-center">
<div id="notesDiv" runat="server">
<div class="form-horizontal">
<div class="form-group">
<label class="col-md-4 control-label">Notes</label>
<div class="col-md-4">
<asp:TextBox ID="tbNotes" runat="server" MaxLength="40" CssClass="form-control"></asp:TextBox>
</div>
</div>
</div>
<asp:LinkButton ID="lnkSave" runat="server" OnClick="lnkSave_Click">
<span aria-hidden="true" class="fa fa-floppy-o"></span> Save
</asp:LinkButton>
<br />
<br />
<asp:LinkButton ID="lnkBack1" runat="server" OnClick="lnkBack_Click">
<span aria-hidden="true" class="fa fa-arrow-circle-left"></span> Back
</asp:LinkButton>
</div>
</div>
<%--End of Notes Row--%>
</ContentTemplate>
</asp:UpdatePanel>
</div>
我的代码是：
namespace ReportingSystemV2.Reporting
{
public partial class GensetDowntime : System.Web.UI.Page
{
ReportingSystemDataContext RsDc = new ReportingSystemDataContext();
protected void Page_Load(object sender, EventArgs e)
{
// Attach to UserControl Event
Master.reportDateChanged += new EventHandler(report_DateChanged);
}
protected void Page_LoadComplete(object sender, EventArgs e)
{
ReportingBase f = (ReportingBase)Page.Master;
if (!Page.IsPostBack)
{
if (f.IdLocation != 0)
{
if (f.endDate < f.startDate)
{
Page.ClientScript.RegisterStartupScript(this.GetType(), Guid.NewGuid().ToString(), "bootstrap_alert.warning('alert-warning', 'Oops!', 'Please select a valid date range..');", true);
}
else
{
BindDowntime();
bindDowntimeSummary();
}
}
else
{
Page.ClientScript.RegisterStartupScript(this.GetType(), Guid.NewGuid().ToString(), "bootstrap_alert.warning('alert-warning', 'Oops!', 'Please select a site..');", true);
}
showDowntimeDetail(false);
}
}
private void report_DateChanged(object sender, EventArgs e)
{
// If the user changes the date lets update the table
BindDowntime();
bindDowntimeSummary();
showDowntimeDetail(false);
}
#region Overview
protected void BindDowntime()
{
// Binds the downtime to the gv
// Hide the downtime ID
ReportingBase f = (ReportingBase)Page.Master;
gridDowntime.Columns[1].Visible = false;
gridDowntime.DataSource = RsDc.FILTEREXEMPTS(f.IdLocation, f.startDate, f.endDate.AddHours(23).AddMinutes(59).AddSeconds(59));
gridDowntime.DataBind();
if (gridDowntime.Rows.Count > 0)
{
// CSS Header Sytle
gridDowntime.UseAccessibleHeader = true;
gridDowntime.HeaderRow.TableSection = TableRowSection.TableHeader;
}
}
protected void bindDowntimeSummary()
{
ReportingBase f = (ReportingBase)Page.Master;
// Binds the summary at the top of the page for the user to see the downtime at a glance
int hrsRun = 0;
TimeSpan tsGrossHours = (f.endDate - f.startDate);
if (f.startDate.Date == f.endDate.Date)
{
tsGrossHours = tsGrossHours.Add(new TimeSpan(24, 0, 0));
hrsRun = Convert.ToInt32(RsDc.ACTUALHOURSRUN(f.IdLocation, f.startDate, f.endDate).FirstOrDefault().ACTUALHOURSRUN);
}
else
{
hrsRun = Convert.ToInt32(RsDc.ACTUALHOURSRUN(f.IdLocation, f.startDate, f.endDate).FirstOrDefault().ACTUALHOURSRUN);
}
lblSumGrossHrs.Text = tsGrossHours.TotalHours.ToString();
lblSumRunHours.Text = hrsRun.ToString();
int totalExempts = 0;
int totalNonExempts = 0;
// Loop Grid
foreach (GridViewRow row in gridDowntime.Rows)
{
DropDownList ddl = new DropDownList();
ddl = row.Cells[5].FindControl("ddlDowntimeExempt") as DropDownList;
CheckBox cbx = new CheckBox();
cbx = row.Cells[6].FindControl("chkDowntimeExclude") as CheckBox;
if (!cbx.Checked)
{
if (ddl.SelectedValue == "1")
{
totalExempts += Convert.ToInt32(row.Cells[4].Text);
}
else
{
totalNonExempts += Convert.ToInt32(row.Cells[4].Text);
}
}
}
TimeSpan tsTotalExempts = new TimeSpan(0, totalExempts, 0);
TimeSpan tsTotalNonExempts = new TimeSpan(0, totalNonExempts, 0);
lblSumTotExempts.Text = ((tsTotalExempts.Days * 24 + tsTotalExempts.Hours).ToString().PadLeft(4, '0') + ":" + tsTotalExempts.Minutes.ToString().PadLeft(2, '0'));
lblSumTotNonExempts.Text = ((tsTotalNonExempts.Days * 24 + tsTotalNonExempts.Hours).ToString().PadLeft(4, '0') + ":" + tsTotalNonExempts.Minutes.ToString().PadLeft(2, '0'));
TimeSpan tsHrsRun = new TimeSpan((int)hrsRun, 0, 0);
lblSumDifference.Text = (tsGrossHours.TotalMinutes - (tsHrsRun.TotalMinutes + tsTotalExempts.TotalMinutes + tsTotalNonExempts.TotalMinutes)).ToString();
DowntimeSummaryDiv.Visible = true;
}
protected void gridDowntime_RowDataBound(object sender, GridViewRowEventArgs e)
{
// Once data is loaded into the gv apply the ddl's for the shutdowns
if (e.Row.RowType == DataControlRowType.DataRow)
{
DropDownList ddl = (DropDownList)e.Row.FindControl("ddlDowntimeExempt");
//ddl.SelectedIndexChanged += new EventHandler(ddlDowntimeExempt_SelectedIndexChanged);
//ddl.AutoPostBack = true;
Label lbl = (Label)e.Row.FindControl("lblDowntimeExempt");
switch (lbl.Text)
{
case "True":
ddl.SelectedValue = "1";
break;
case "False":
ddl.SelectedValue = "0";
break;
default:
ddl.SelectedValue = "-1";
break;
}
}
}
protected void gridDowntime_SelectedIndexChanged(object sender, EventArgs e)
{
// User selected a shutdown, show its details
bindDowntimeDetail();
showDowntimeDetail(true);
}
protected void ddlDowntimeExempt_SelectedIndexChanged(object sender, EventArgs e)
{
// Applies the values selected in the exempt DDL to the database value
DropDownList ddl = (DropDownList)sender;// <--Breakpoint
GridViewRow gvrow = (GridViewRow)ddl.NamingContainer;
int exempt_id = int.Parse(gridDowntime.DataKeys[gvrow.RowIndex].Value.ToString());
bool? value = new bool?();
if (ddl.SelectedValue.ToString() == "1")
{
value = true;
LogMe.LogUserMessage(string.Format("Exempt ID:{0}, set to Exempt.", exempt_id));
}
else if (ddl.SelectedValue.ToString() == "0")
{
value = false;
LogMe.LogUserMessage(string.Format("Exempt ID:{0}, set to Non-Exempt.", exempt_id));
}
else
{
value = null;
LogMe.LogUserMessage(string.Format("Exempt ID:{0}, set to Unverified.", exempt_id));
}
RsDc.UPDATEISEXEMPT(exempt_id, value);
// Update the gv
BindDowntime();
}
protected void chkDowntimeExclude_CheckedChanged(object sender, EventArgs e)
{
// When the Exclude checkbox is changed, update the Db
CheckBox chk = (CheckBox)sender; // <--Breakpoint
GridViewRow gvrow = (GridViewRow)chk.NamingContainer;
int exempt_id = int.Parse(gridDowntime.DataKeys[gvrow.RowIndex].Value.ToString());
RsDc.updateIsExcluded(exempt_id, chk.Checked);
if (chk.Checked)
{
LogMe.LogUserMessage(string.Format("Exempt ID:{0}, has been Excluded.", exempt_id));
}
else
{
LogMe.LogUserMessage(string.Format("Exempt ID:{0}, has been Included.", exempt_id));
}
BindDowntime();
bindDowntimeSummary();
}
protected void showDowntimeDetail(bool show)
{
// Shows or Hides a specific shutdowns detail
downtimeDiv.Visible = !show;
DowntimeSummaryDiv.Visible = !show;
detailDiv.Visible = show;
notesDiv.Visible = show;
downtimeValueDiv.Visible = show;
}
#endregion
#region Details
protected void bindDowntimeDetail()
{
// Bind the detail for the selected shutdown
// Get the values from the gv's datakeys
int id_location = int.Parse(gridDowntime.SelectedDataKey[1].ToString());
DateTime dtdown = DateTime.Parse(gridDowntime.SelectedDataKey[4].ToString());
DateTime dtup = DateTime.Parse(gridDowntime.SelectedDataKey[5].ToString());
int exempt_id = int.Parse(gridDowntime.SelectedDataKey[0].ToString());
int adjust = int.Parse(ddlAdjust.SelectedValue);
// Get the detail & apply
DB db = new DB();
gridDowntimeDetail.DataSource = db.getAllReasonForDownTimeAppend(id_location, dtdown, dtup, adjust, exempt_id);
gridDowntimeDetail.DataBind();
//CSS Header Sytle
gridDowntimeDetail.UseAccessibleHeader = true;
gridDowntimeDetail.HeaderRow.TableSection = TableRowSection.TableHeader;
//Notes
bindDowntimeNotes(exempt_id);
bindDowntimeDetailsSummary(exempt_id);
}
protected void bindDowntimeDetailsSummary(int id)
{
gridDowntimeRecalc.DataSource = (from s in RsDc.Exempts where s.ID == id select s).ToList();
gridDowntimeRecalc.DataBind();
//CSS Header Sytle
gridDowntimeRecalc.UseAccessibleHeader = true;
gridDowntimeRecalc.HeaderRow.TableSection = TableRowSection.TableHeader;
}
protected void bindDowntimeNotes(int id)
{
var query = (from s in RsDc.Exempts where s.ID == id select s.Details).Single();
if (query != null)
{
tbNotes.Text = query.ToString();
}
}
protected void gridDowntimeDetail_RowDataBound(object sender, GridViewRowEventArgs e)
{
// Highlights the GCB Open & GCB Closed Events
// Also enables the mouse over highlight & click functionality
if (e.Row.RowType == DataControlRowType.DataRow)
{
if (e.Row.Cells[2].Text == "GCB opened")
{
e.Row.CssClass = "danger";
}
else if (e.Row.Cells[2].Text == "GCB closed")
{
e.Row.CssClass = "info";
}
else
{
e.Row.CssClass = "";
e.Row.Attributes.Add("style", "cursor:pointer;");
e.Row.Attributes.Add("onclick", "this.style.backgroundColor='orange';");
e.Row.Attributes.Add("onmouseover", "this.style.backgroundColor='#c8e4b6'");
e.Row.Attributes.Add("onmouseout", "this.style.backgroundColor=''");
}
}
}
protected override void Render(HtmlTextWriter writer)
{
// Trigger an event when a row is clicked
foreach (GridViewRow row in gridDowntimeDetail.Rows)
{
if (row.RowType == DataControlRowType.DataRow)
{
// Set the last parameter to True
// to register for event validation.
row.Attributes["onclick"] = Page.ClientScript.GetPostBackClientHyperlink(gridDowntimeDetail, "Up$" + row.RowIndex, true);
}
}
base.Render(writer);
}
protected void gridDowntimeDetail_RowCommand(object sender, GridViewCommandEventArgs e)
{
// Handles what will happen when a selected row is clicked
// But first - is this a request to go back?
if (e.CommandName == "Back")
{
// Return to the Downtime View
// Hide the details
showDowntimeDetail(false);
//CSS Header Sytle
gridDowntime.UseAccessibleHeader = true;
gridDowntime.HeaderRow.TableSection = TableRowSection.TableHeader;
}
else if(e.CommandName == "Up")
{
// Get the selected row index
int rowIndex = Convert.ToInt32(e.CommandArgument.ToString());
// Get the user selected new details
int exempt_id = Convert.ToInt32(gridDowntimeDetail.DataKeys[rowIndex].Value);
DateTime newUp = DateTime.ParseExact(gridDowntimeDetail.Rows[rowIndex].Cells[1].Text, "dd/MM/yyyy HH:mm:ss.fff", CultureInfo.InvariantCulture);
string reason = gridDowntimeDetail.Rows[rowIndex].Cells[2].Text;
// Get the original details from db.
var orig = (from t in RsDc.getExemptsUpDown(exempt_id)
select new { DtDown = t.DTDOWN, DtUp = t.DTUP }).SingleOrDefault();
DateTime Down = Convert.ToDateTime(orig.DtDown);
//DateTime Up = Convert.ToDateTime(orig.DtUp);
if (newUp >= Down)
{
int totalmins = Convert.ToInt32((newUp - Down).TotalMinutes);
// Update the DB
RsDc.updateExempt(exempt_id, newUp, totalmins, reason, false);
LogMe.LogUserMessage(string.Format("Exempt ID:{0}, Uptime has been updated. Reason:{1}, Uptime:{2}.", exempt_id, reason, newUp.ToString()));
// Highlight & Refresh times
gridDowntimeDetail.Rows[rowIndex].CssClass = "info";
bindDowntimeDetailsSummary(exempt_id);
bindDowntimeDetail();
showDowntimeDetail(true);
Page.ClientScript.RegisterStartupScript(this.GetType(), Guid.NewGuid().ToString(), "bootstrap_alert.warning('success', 'Success!', 'The record has been updated!');", true);
}
else
{
// User Feedback Error
}
}
}
protected void lnkReset_Click(object sender, EventArgs e)
{
// Reset the shutdown values back to there defaults
int ExemptId = Convert.ToInt32(gridDowntimeDetail.DataKeys[0].Value);
RsDc.resetExempt(ExemptId);
LogMe.LogUserMessage(string.Format("Exempt ID:{0}, has been Reset.", ExemptId));
bindDowntimeDetailsSummary(ExemptId);
bindDowntimeDetail();
showDowntimeDetail(true);
Page.ClientScript.RegisterStartupScript(this.GetType(), Guid.NewGuid().ToString(), "bootstrap_alert.warning('success', 'Success!', 'The record has been reset!');", true);
}
protected void lnkBack_Click(object sender, EventArgs e)
{
// Return to the Downtime View
// Hide the details
showDowntimeDetail(false);
//CSS Header Sytle
gridDowntime.UseAccessibleHeader = true;
gridDowntime.HeaderRow.TableSection = TableRowSection.TableHeader;
}
protected void ddlAdjust_SelectedIndexChanged(object sender, EventArgs e)
{
// Adjust the viewing window (minutes)
bindDowntimeDetail();
showDowntimeDetail(true);
}
protected void lnkSave_Click(object sender, EventArgs e)
{
// Save the Note to the Db
int ExemptId = int.Parse(gridDowntime.SelectedDataKey[0].ToString());
RsDc.setExemptDetails(ExemptId, tbNotes.Text);
LogMe.LogUserMessage(string.Format("Exempt ID:{0}, Notes have been updated '{1}'.", ExemptId, tbNotes.Text));
Page.ClientScript.RegisterStartupScript(this.GetType(), Guid.NewGuid().ToString(), "bootstrap_alert.warning('success', 'Success!', 'The record has been saved!');", true);
}
#endregion
}
}
任何帮助，不胜感激。谢谢
我相信
我自己已经找到了这个答案，经过进一步调试，我发现我在更改GridView日期范围的Control在更改CheckBox值或DropDownList值时被触发。因此，CheckBox_CheckChanged和DropDownList_SelectedIndexChanged事件没有被解雇。
我发现这是因为我在页面上有多个"更新面板"，所有这些面板都是同时触发的。 因此，通过添加：
if (Request["__EVENTTARGET"] == UpdatePanelDateChanged.ClientID)
{
// Fire date changed event here..
}
我能够阻止我的"dateChanged"函数触发，除非在我的日期选择Control中对UpdatePanel进行特定的PostBack调用。
请参阅我的问题：有关详细信息，C# ASP.NET CheckBox_OnCheckedChanged未按预期触发。
我认为你应该使用类似的东西
<asp:UpdatePanel ID="updPanelDowntime" runat="server">
<ContentTemplate>
<asp:DropDownList ID="ddlAdjust" runat="server">
</asp:DropDownList>
</ContentTemplate>
<Triggers>
<asp:PostBackTrigger ControlID="ddlAdjust" />
</Triggers>
</asp:UpdatePanel>
UpdatePanel停止回发。您必须手动指定异步和完全回发触发器。请参阅这些链接 控制事件未从更新面板中触发 和 按钮单击在更新面板中不起作用