Wie kann ich mit jquery ein <panel> ein- / ausblenden?
Ich bemühe mich sehr, ein Panel (das zwei Beschriftungen enthält und beim Laden der Seite ausgeblendet wird) mit einem Klick auf eine Schaltfläche anzuzeigen, erhalte aber keinen Erfolg.
Wenn ich auf einen Button klicke (id = Button1), sollte ein Panel angezeigt werden (id = anspanel), aber das passiert nicht so. Stattdessen bleibt es so, wie es ist, d. H. Bei einem Tastenklick passiert nichts. Ich kann nicht herausfinden warum. Schau dir meinen Code an. Zeigen Sie mir, wo ich Fehler mache und was die Lösung ist.
.aspx: -
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Test.aspx.cs" Inherits="Student_Test" %>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
<link rel="stylesheet" href="http://code.jquery.com/ui/1.8.3/themes/base/jquery-ui.css" />
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
<script type="text/javascript" src="http://code.jquery.com/ui/1.8.3/jquery-ui.js"></script>
<script type="text/javascript">
var currentTab = 0;
$(function () {
$("#tabs").tabs({
select: function (e, i) {
currentTab = i.index;
}
});
});
$("#btnNext").live("click", function () {
var tabs = $('#tabs').tabs();
var c = $('#tabs').tabs("length");
currentTab = currentTab == (c - 1) ? currentTab : (currentTab + 1);
tabs.tabs('select', currentTab);
$("#btnPrevious").show();
if (currentTab == (c - 1)) {
$("#btnNext").hide();
} else {
$("#btnNext").show();
}
});
$("#btnPrevious").live("click", function () {
var tabs = $('#tabs').tabs();
var c = $('#tabs').tabs("length");
currentTab = currentTab == 0 ? currentTab : (currentTab - 1);
tabs.tabs('select', currentTab);
if (currentTab == 0) {
$("#btnNext").show();
$("#btnPrevious").hide();
}
if (currentTab < (c - 1)) {
$("#btnNext").show();
}
});
$(function () {
//$("#Panel2").hide();
document.getElementById('form1').onsubmit = function () {
return false;
}//Avoid Reloading
$("#Button1").click(function () {
if ($('#anspanel').is(":hidden")) {
$('#anspanel').show();
}
else {
$('#anspanel').hide();
}
if ($("#Button1").val() == "Show Answer") {
$("#Button1").val("Hide Answer");
} else {
$("#Button1").val("Show Answer");
}
});
});
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<div id="tabs">
<ul>
<li><a href="#tabs-1">Tab 1</a></li>
<li><a href="#tabs-2">Tab 2</a></li>
<li><a href="#tabs-3">Tab 3</a></li>
<li><a href="#tabs-4">Tab 4</a></li>
<li><a href="#tabs-5">Tab 5</a></li>
</ul>
<div id="tabs-1">
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false" >
<Columns>
<asp:TemplateField>
<ItemTemplate>
<asp:Panel ID="Panel1" runat="server">
<asp:Label ID="Label1" runat="server" Text='<%#Eval("Question") %>'></asp:Label>
<br />
<br />
<br />
<span>A-</span> <asp:Label ID="Label2" runat="server" Text='<%#Eval("Option1")%>'></asp:Label>
<br />
<br />
<span>B-</span> <asp:Label ID="Label3" runat="server" Text='<%#Eval("Option2")%>'></asp:Label>
<br />
<br />
<span>C-</span> <asp:Label ID="Label4" runat="server" Text='<%#Eval("Option3")%>'></asp:Label>
<br />
<br />
<span>D-</span> <asp:Label ID="Label5" runat="server" Text='<%#Eval("Option4")%>'></asp:Label>
<br />
<br />
<asp:Button ID="Button1" runat="server" Text="Show Answer" />
<br />
<asp:Panel id="anspanel" runat="server">
<span>Correct Answer is :-</span><asp:Label ID="Label6" runat="server" Text='<%#Eval("CorrectAns")%>'></asp:Label>
<br />
<br />
<asp:Label ID="Label7" runat="server" Text='<%#Eval("Explanation")%>'></asp:Label>
</asp:Panel>
</asp:Panel>
<br />
<br />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
</div>
<div id="tabs-2">
Tab 2 Content
</div>
<div id="tabs-3">
Tab 3 Content
</div>
<div id="tabs-4">
Tab 4 Content
</div>
<div id="tabs-5">
Tab 5 Content
</div>
</div>
<input type="button" id="btnPrevious" value="Previous" style = "display:none"/>
<input type="button" id="btnNext" value="Next" />
</div>
</form>
</body>
</html>.aspx.cs: -
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data.SqlClient;
using System.Data;
using System.Configuration;
public partial class Student_Test : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
GridView1.DataSource = GetData("SELECT top 2 Question, Option1, Option2, Option3, Option4, CorrectAns, Explanation FROM Questions");
GridView1.DataBind();
foreach (GridViewRow row in GridView1.Rows)
{
if (row.RowType == DataControlRowType.DataRow)
{
Panel panel1 = (Panel)row.FindControl("Panel1");
Panel anspanel = (Panel)panel1.FindControl("anspanel");
anspanel.Style.Add("display", "none");
}
}
}
}
private DataSet GetData(string query)
{
string conString = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;
SqlCommand cmd = new SqlCommand(query);
using (SqlConnection con = new SqlConnection(conString))
{
using (SqlDataAdapter sda = new SqlDataAdapter())
{
cmd.Connection = con;
sda.SelectCommand = cmd;
using (DataSet ds = new DataSet())
{
sda.Fill(ds);
return ds;
}
}
}
}
}
ERROR :
Server Error in '/' Application.
Object reference not set to an instance of an object.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.
Source Error:
Line 24: Panel panel1 = (Panel)row.FindControl("Panel1");
Line 25: Panel anspanel = (Panel)panel1.FindControl("anspanel");
Line 26: anspanel.Style.Add("display", "none");
Line 27: }
Line 28: }
Source File: e:\Way2Success\Student\Test.aspx.cs Line: 26
Stack Trace:
[NullReferenceException: Object reference not set to an instance of an object.]
Student_Test.Page_Load(Object sender, EventArgs e) in e:\Way2Success\Student\Test.aspx.cs:26
System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +51
System.Web.UI.Control.OnLoad(EventArgs e) +95
System.Web.UI.Control.LoadRecursive() +59
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +2952