Develop Reference

In Paged Listview CheckBox_CheckedChanged event not working

The Problem is when I check the checkbox it works great, but when I check the checkbox on next page. previous page check boxes gets unchecked.
Checked box Checked/Unchecked event fires CheckedChanged event. But when I check the checkbox in listview next page of listview it uncheck's the checkboxes of listview previous Page.
ListView.aspx Code
<table class=" example1 table table-bordered table-striped">
<thead>
<tr>
<th>Sr no.</th>
<th>Parent Category</th>
<th>Title</th>
<th>Description</th>
<th>Image</th>
<th>Show on Homepage</th>
<th>Edit</th>
<th>Delete</th>
</tr>
</thead>
<tbody>
<asp:ListView ID="ListCourse" runat="server" OnItemCommand="ListCourse_ItemCommand" DataKeyNames="CID">
<LayoutTemplate>
<tr id="ItemPlaceholder" runat="server">
</tr>
</LayoutTemplate>
<ItemTemplate>
<tr class="gradeA">
<td>
<asp:Label ID="lblSrno" runat="server" Text='<%# Container.DataItemIndex+1 %>'></asp:Label>
</td>
<td>
<asp:Label ID="lbl" runat="server" Text='<%# GetCourse(Convert.ToInt32( Eval("CatID"))) %>'></asp:Label>
</td>
<td>
<asp:Label ID="Lbltitle" runat="server" Text='<%# Eval("Title") %>'></asp:Label>
<asp:Label ID="lablc" runat="server" Visible="false" Text='<%# Eval("CID") %>'></asp:Label>
</td>
<td>
<asp:Label ID="lblDescrption" runat="server" Text='<%# (Eval("Description").ToString().Length <=200)?Eval("Description").ToString(): Eval("Description").ToString().Substring(0, 200) + "..."%>'></b></asp:Label>
</td>
<td>
<img class="img_show " src="/Gallery/<%# Eval("Image")%>">
</td>
<td>
<asp:CheckBox ID="CheckCourse" runat="server" Style="margin-left: 50px;" OnCheckedChanged="CheckCourse_CheckedChanged" AutoPostBack="true" />
</td>
<td>
<asp:LinkButton ID="LinkEdit" runat="server" PostBackUrl='<%# "Add_New_Course.aspx?ID="+ Eval("CID")%>'>Edit</asp:LinkButton>
</td>
<td>
<asp:LinkButton ID="LinkDelete" runat="server" CommandName="DeleteCourse" CommandArgument='<%# Eval("CID") %>' OnClientClick='return confirm("Do you want to delete record ??")'> Delete</asp:LinkButton>
</td>
</tr>
</ItemTemplate>
</asp:ListView>
</tbody>
</table>
Code Behind CheckedChanged
protected void CheckCourse_CheckedChanged(object sender, EventArgs e)
{
CheckBox checkhome = (CheckBox)sender;
ListViewItem item = (ListViewItem)checkhome.NamingContainer;
ListViewDataItem dataItem = (ListViewDataItem)item;
string code = ListCourse.DataKeys[dataItem.DisplayIndex].Value.ToString();
int CID = Convert.ToInt32(code);
Course_Master objnew = DB.Course_Master.Single(p => p.CID == CID);
bool IsHome = CheckOnHome(CID);
if (IsHome == true)
{
if (checkhome.Checked == false)
{
objnew.ShowOnHomePage = false;
}
}
else
{
if (checkhome.Checked == true)
{
objnew.ShowOnHomePage = true;
}
}
DB.SaveChanges();
}

It doesn't fire because when the postback fires the server doesn't know the previous state of the checkbox, so it doesn't know if it's changed or not.
Try to set the default value to false and it should work
<asp:CheckBox ID="CheckCourse" runat="server" Checked="false" Style="margin-left: 50px;" OnCheckedChanged="CheckCourse_CheckedChanged" AutoPostBack="true" />

You need to save ids somewhere of checked item from the list. As when you move to the page 2 of ListView it lost its previous state.
Store data in viewstate and load it from there. To read and to bind it, you would need to handle PagePropertiesChanging and ItemDataBound event handlers of ListView.
Here is a good explaination regarding Maintaining the state of checkboxes in ListView
Please give +1 if it helped. Cheers!

Thank you Guys for the help. I solved it using some simple procedure's by removing the check-boxes from the ListView and adding text instead of it regarding whether the checkbox is checked or not(Yes/No). As I thought it will the easiest way to solve my problem.

Checkbox state not changed on postback

I have the following mark up for a User Control (.ascx)
<table>
<tr>
<td>
<asp:Label ID="Label1" runat="server" Text="Select Logical Symbol to Search:"></asp:Label>
</td>
<td>
<asp:DropDownList ID="ddlComponentType" runat="server"
onselectedindexchanged="ddlComponentType_SelectedIndexChanged" AutoPostBack="true">
</asp:DropDownList>
</td>
<td>
<asp:CheckBox ID="chkAdvSearchAllLibs" runat="server" ToolTip="Check this box to search all available libraries" Text="Search All Libraries"/>
</td>
</tr>
<tr>
<td>
<asp:Label ID="Label2" runat="server" Text="Search by Logical Symbol Properties:"></asp:Label>
</td>
<td>
</td>
</tr>
On page Load
protected void Page_Load(object sender, EventArgs e)
{
SearchResults(ref attributeSearch, compTypeID);
}
where SearchResults is
private void SearchResults(ref string attributeSearch, int compTypeID)
{
DataTable dtResults = this.AdvancedSearchControl.GetSearchResults(ref attributeSearch, compTypeID);
}
And in my UserControl.ascx.cs
public DataTable GetSearchResults(ref string _attrVals, int compTypeID)
{
//Other Logic Goes Here
IEnumerable<Model.ComponentInfo.ComponentType> compTypeResult = from compTypes in BLLibrary.GetComponentTypeBasedOnLib(this.CurrentLibraryId, this.CurrentLibrary, this.chkAdvSearchAllLibs.Checked) select compTypes.Value;
}
this.chkAdvSearchAllLibs.Checked is always false no matter if the check-box is checked on page and posted back or not.

Server side:
Add AutoPostBack="True" to the CheckBox. It's not posting back.
Client side:
<asp:CheckBox runat="server" ID="cb" onclick="checkboxchanged(this);" />
function checkboxchanged( sender ) {
if ( sender.checked ) {
// clicked and checked
} else {
// clicked and unchecked
}
}

Repeater list is not getting updated in OnItemCommand method

I have a repeater control. In OnItemCommand method of repeater, after doing some operations I am trying to refresh the repeater list so that it could show me the updated list. But somehow repeater list is not updated in method. However when I reload the page then repeater list gets updated with most recent items.
ASPX:
<asp:Label ID="Message1" runat="server" ForeColor="Blue" Text=""></asp:Label>
<div id="ListingAgentsData" class="panel panel-default" style="width: 920px;">
<asp:Repeater ID="rptagentList" runat="server" OnItemCommand="rptagentList_OnItemCommand">
<HeaderTemplate>
<table id="results1" cellpadding="4" cellspacing="1" width="100%">
<tr>
<td>
<strong>AgentID</strong>
</td>
<td>
<strong>Email</strong>
</td>
<td>
<strong>FullName</strong>
</td>
<td>
<strong>Driver License/Passport</strong>
</td>
<td>
<strong>Action</strong>
</td>
</tr>
</HeaderTemplate>
<ItemTemplate>
<tr>
<td>
<asp:Label ID="lblDayofweek" runat="server" Text='<%#Eval("AgentID")%>'></asp:Label>
</td>
<td>
<asp:Label ID="lblTime" runat="server" Text='<%#Eval("Email")%>'></asp:Label>
</td>
<td>
<asp:Label ID="lblCharges" runat="server" Text='<%#Eval("FullName")%>'></asp:Label>
</td>
<td>
<asp:Label ID="Label1" runat="server" Text='<%#Eval("DriverLicense")%>'></asp:Label>
</td>
<td>
<asp:LinkButton ID="ibtn" runat="server" Text="Approve" CommandName="Approve" CommandArgument='<%#Eval("AgentID")%>' />
<asp:LinkButton ID="LinkButton1" runat="server" Text="Reject" CommandName="Reject" CommandArgument='<%#Eval("AgentID")%>' />
</td>
</tr>
</ItemTemplate>
<FooterTemplate>
</table>
</FooterTemplate>
</asp:Repeater>
.CS:
protected void Page_Load(object sender, EventArgs e)
{
if (Session["Username"] == null)
Response.Redirect("../Login/Default.aspx");
else
{
Init();
}
}
protected void rptagentList_OnItemCommand(object source, RepeaterCommandEventArgs e)
{
try
{
if (e.CommandName == "Approve")
{
int agentId = Convert.ToInt32(e.CommandArgument);
GM gm = new GM();
if (gm.ApproveListingAgent(agentId))
{
Message1.Text = "Listing Agent with ID:"+agentId+" is approved!";
Init();
}
}
else if (e.CommandName == "Reject")
{
}
}
catch (Exception ex)
{
throw ex;
}
}
private void Init()
{
ListingAgent Agent = new ListingAgent();
DataTable dt = Agent.getPendingListingAgents();
if (dt.Rows.Count > 0)
{
rptagentList.DataSource = dt;
rptagentList.DataBind();
}
}
What am I missing?
Please help!

check value of checkboxes inside listview

I have a ListView with a checkbox field inside that gets the id set dynamically.
I also have a button that when pressed needs to check if any of the checboxes have been checked but I'm not sure how to get this done.
Any idea on how I can get this done?
Thanks
This is my code:
<asp:ListView ID="ListView1" runat="server" DataKeyNames="Id"
DataSourceID="EntityDataSource1" EnableModelValidation="True">
<ItemTemplate>
<tr>
<td class="firstcol">
<input id='Checkbox<%# Eval("Id") %>' type="checkbox" />
</td>
</tr>
</ItemTemplate>
<LayoutTemplate>
<table width="100%" border="0" cellspacing="0" cellpadding="0">
<tr>
<th width="50" scope="col" class="firstcol">
</th>
</tr>
<tr ID="itemPlaceholder" runat="server"></tr>
</table>
<asp:Button ID="btnDownload" runat="server" Text="Download" Height="26px"
onclick="btnDownload_Click" />
</LayoutTemplate>
</asp:ListView>
protected void btnDownload_Click(object sender, EventArgs e)
{
???????
}

disclaimer: I'm more of a back-end/wpf developer. There are likely more elegant solutions, but this seems to work.
Change your checkbox id so it is not unique (sorry, this will break w3c validation) and set it to runat server and set the value of the CheckBox to your data source's Id:
<ItemTemplate>
<tr>
<td class="firstcol">
<label runat="server"><%# Eval( "Id" ) %></label>
<input id="MyCheckBox" value='<%# Eval("Id") %>'
type="checkbox" runat="server" />
</td>
</tr>
</ItemTemplate>
You can then iterate through the ListView's items collection and find the CheckBoxes:
protected void btnDownload_Click( object sender, EventArgs e )
{
foreach( ListViewDataItem item in ListView1.Items )
{
var chk = item.FindControl( "MyCheckBox" ) as System.Web.UI.HtmlControls.HtmlInputCheckBox;
if( chk != null && chk.Checked )
{
string value = chk.Value;
}
}
}
If you wanted a bit of Linq:
protected void btnDownload_Click( object sender, EventArgs e )
{
var checkedCheckBoxes = ListView1.Items.Select( x => x.FindControl( "MyCheckBox" ) as HtmlInputCheckBox )
.Where( x => x != null && x.Checked );
// do stuff with checkedCheckBoxes
}

Radio buttons not working when binded with DataList control

When i tries to bind a radio button in a datalist it becomes multiselect as its name property becomes different even when i used GroupName to be same.
How can i make it act as radio button only.
<asp:DataList ID="dlRoomNo" runat="server" RepeatColumns="4">
<ItemTemplate>
<div class="orboxfour">
<ul class="boxfour">
<li>
<asp:RadioButton ID="rdoRoomNo" GroupName="roomNo"
Text='<%#Eval("Room No")%>' runat="server" />
</li>
</ul>
</div>
</ItemTemplate>
</asp:DataList>

There's a number of suggestions in the answers to this question.
I've solved it with a bit of jQuery, though the way I did it probably isn't the best way!
In my markup, I have a script block with
function SetUniqueRadioButton(current)
{
$('input:radio').attr('checked', false);
current.checked = true;
}
and then attached the script to a radio button in my code-behind in the ItemDataBound event
String uniqueRadioButtonScript;
RadioButton radioButton;
uniqueRadioButtonScript = "javascript:SetUniqueRadioButton(this);";
if (e.Row.RowType == DataControlRowType.DataRow)
{
radioButton = (RadioButton)e.Row.FindControl("MyRadioButton");
radioButton.Attributes.Add("onclick", uniqueRadioButtonScript)
}

the best option is like this:
1. Add script
function fnrad(rbtn) {
var radioList = document.getElementsByTagName("input");
for (var i = 0 ; i < radioList.length; i++) {
if (radioList[i].type == "radio") {
radioList[i].name = 'a';
radioList[i].setAttribute("Checked","");
}
}
rbtn.setAttribute("Checked", "checked");
}
Datalist will be like this:
<asp:DataList ID="dlEmails" RepeatLayout="Flow" runat="server">
<HeaderTemplate>
<table>
<tr>
<th>Select Email Address </th>
<th>Status</th>
</tr>
</HeaderTemplate>
<ItemTemplate>
<tr>
<td>
<asp:RadioButton ID="rbtnSelect" Text='<%#Eval("Emails") %>' onclick='fnrad(this);' GroupName="a" Checked='<%#Eval("Primary") %>' runat="server" /><br />
(<asp:Label ID="lblId" runat="server" Text='<%#Eval("Verified") %>'> </asp:Label>)
</td>
<td valign="middle">
<asp:Label ID="Label2" Style="display: none;" runat="server" Text='<%#Eval("Id") %>'> </asp:Label>
<asp:Label ID="Label1" runat="server" Text='<%#Eval("Main") %>'> </asp:Label>
</td>
</tr>
</ItemTemplate>
<FooterTemplate>
</table>
</FooterTemplate>
</asp:DataList>