Develop Reference

OnChanged even't isn't firing (AJAX raiting control) inside a datalist

I'm using the latest ajax toolkit version. I've tried to put the rating control in a datalist, but the OnChanged event for some reason isn't firing.
That's the normal ASPX.NET page:
<asp:DataList ID="DataListEpisodes" runat="server" Style="position: relative; bottom: 330px;" Visible="False" RepeatColumns="1" OnItemDataBound="DataListEpisodes_ItemDataBound" DataKeyField="EpisodeID" OnItemCommand="DataListEpisodes_ItemCommand">
<ItemTemplate>
<table>
<tr>
<td>
<td>
<asp:Image ID="ImageEpisodeImage" class="EpisodeImage" runat="server" ImageUrl='<%# Eval("EpisodeImage", "https://image.tmdb.org/t/p/original{0}") %>' />
</td>
</td>
<td>
<asp:Label ID="LabelEpisodeNumber" runat="server" Style="font-family: Gotham Ultra; font-size: 25px; font-weight: bold;"
Text='<%# Eval("SeasonNumber", "Season {0}") + ", " + Eval ("EpisodeNumber", "Episode {0}") %>'></asp:Label>
<br />
<asp:Label ID="LabelEpisodeName" Style="font-family: Proxima Nova Semibold; font-size: 20px; font-weight: bold;" runat="server" Text='<%# Bind("EpisodeName") %>'></asp:Label>
<br />
<asp:TextBox ID="TextBox1" runat="server" ReadOnly="True" class="LabelOverview" Text='<%# Bind("EpisodeOverview") %>' TextMode="MultiLine"></asp:TextBox>
<br />
<asp:Button ID="ButtonAddEpisode" class="ButtonAddEpisode" runat="server" Text="Add Episode To Watch History" CommandName="AddEpisode" />
<asp:Button ID="ButtonRemoveEpisode" class="ButtonAddEpisode" runat="server" Text="Remove Episode From Watch History" CommandName="RemoveEpisode" />
<br />
<asp:Button ID="ButtonWatchListAdd" class="ButtonEpisodeWatchList" runat="server" Text="Add Episode To Future Watch List" CommandName="AddWatchList" />
**<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<ajaxToolkit:Rating ID="Rating1" OnChanged="OnRatingChanged" style="position: relative;right: 301px;top: 16px;" AutoPostBack="true" runat="server"
StarCssClass="Star" EmptyStarCssClass="Star"
FilledStarCssClass="FilledStar" WaitingStarCssClass="Star">
</ajaxToolkit:Rating>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="Rating1" EventName="Click" />
</Triggers>
</asp:UpdatePanel>**
</tr>
</table>
<br />
<br />
<br />
<br />
</ItemTemplate>
</asp:DataList>
and that's the codebehind:
protected void OnRatingChanged(object sender, AjaxControlToolkit.RatingEventArgs e)
{
int rowIndex = ((sender as AjaxControlToolkit.Rating).NamingContainer as DataListItem).ItemIndex;
int RatingChosed = Rating1.CurrentRating;
int EpisodeID = Convert.ToInt32(DataListEpisodes.DataKeys[rowIndex].ToString());
}
Thank you if someone can help me :D

Get modal popup values in gridview row textbox

I have a gridview with dynamic controls. Resource name is something that I am picking up from Active directory. Search filter works in a way where you have to enter lastname, firstname and onlclick of lookup it will search. If there are more than one record a modalpopup will be displayed with dropdownlist with options to select from.
The issue is that I am unable to get the dropdown values populated into textbox present in gridview. I need this dropdown value in correct selected row's textbox.
Code behind:
protected void gvProjectResource_RowCommand(object sender, GridViewCommandEventArgs e)
{
if (e.CommandName == "Lookup")
{
GridViewRow clickedRow = ((LinkButton)e.CommandSource).NamingContainer as GridViewRow;
TextBox t2 = ((TextBox)clickedRow.FindControl("t2"));
DataTable dt = globalObj.FindPersons(t2.Text.Split(',')[0].Trim(), t2.Text.Split(',')[1].Trim());
if (dt.Rows.Count > 1)
{
mpFindPerson.Show();
ddlPersons.Items.Clear();
ddlPersons.Items.Add(new ListItem { Value = "0", Text = "-Select User-" });
ddlPersons.DataSource = dt;
dt.Columns.Add("FullName", typeof(string), "DisplayName + ' | ' + MSID");
ddlPersons.DataTextField = "FullName";
ddlPersons.DataValueField = "MSID";
ddlPersons.DataBind();
}
else
{
t2.Text = dt.Rows[0].ItemArray[0].ToString();
}
}
if (e.CommandName == "Del")
{
}
}
protected void btnSelectPerson_Click(object sender, EventArgs e)
{
TextBox t2 = (gvProjectResource.SelectedRow.FindControl("t2") as TextBox);
t2.Text = ddlPersons.SelectedItem.Text;
mpFindPerson.Hide();
}
ASPX Code:
<div id="four">
<fieldset style="border: solid; border-width: thin; height: 220px; border-color: #a8a8a8;">
<legend id="Legend11" runat="server" visible="true" style="width: auto; margin-bottom: 0px; font-size: 12px; font-weight: bold; color: #1f497d;"> Project Resources </legend>
<div style="height: 210px; overflow: auto;">
<asp:GridView ID="gvProjectResource" Width="88%" HeaderStyle-Font-Size="X-Small" CssClass="labels" runat="server"
ShowFooter="true" AutoGenerateColumns="false" Style="margin-right: auto; margin-left:7px;"
OnRowDataBound="gvProjectResource_RowDataBound"
OnRowCommand="gvProjectResource_RowCommand" >
<Columns>
<asp:TemplateField HeaderText="Role" ItemStyle-VerticalAlign="Top" FooterStyle-VerticalAlign="Top" ItemStyle-Width="50%">
<ItemTemplate>
<asp:Label ID="lblRole" runat="server" Text='<%# Eval("role") %>' Visible="false" />
<asp:DropDownList ID="ddlRole" Height="23px" Width="98%" runat="server" CssClass="DropDownListStyleOverview"></asp:DropDownList>
</ItemTemplate>
<FooterTemplate>
<asp:DropDownList ID="ddlRole2" Height="23px" Width="98%" runat="server" CssClass="DropDownListStyleOverview"></asp:DropDownList>
</FooterTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Resource Name" ItemStyle-VerticalAlign="Top" FooterStyle-VerticalAlign="Top" ItemStyle-Width="50%">
<ItemTemplate>
<asp:TextBox ID="t1" Height="23px" Width="98%" runat="server" ></asp:TextBox>
</ItemTemplate>
<FooterTemplate>
<asp:TextBox ID="t2" Height="23px" Width="68%" runat="server"></asp:TextBox>
<asp:LinkButton runat="server" Text="Lookup" CommandName="Lookup" />
</FooterTemplate>
</asp:TemplateField>
<asp:TemplateField ItemStyle-VerticalAlign="Top" ItemStyle-Width="5%">
<ItemTemplate>
<asp:LinkButton runat="server" Text="Delete" CommandName="Del" />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<br />
<div style="text-align: right;">
<asp:LinkButton runat="server" Text="Add New" ID="LinkButton2" CssClass="labels"></asp:LinkButton>
</div>
</div>
<asp:Button runat="server" ID="btnModalPopUpSearch" Style="display: none" />
<AjaxToolkit:ModalPopupExtender ID="mpFindPerson"
BehaviorID="mpFindPersonBehav"
runat="server"
DropShadow="true"
BackgroundCssClass="modalBackground"
PopupControlID="pnlFindPerson"
TargetControlID="btnModalPopUpSearch">
</AjaxToolkit:ModalPopupExtender>
<asp:Panel runat="Server" ID="pnlFindPerson" CssClass="modalPopup" style="position:relative;">
<div class="labels" runat="server" style="text-align:center; position:absolute; top:20%; height:10em; margin-top:auto; margin-left:20px;">
<asp:DropDownList ID="ddlPersons" runat="server" AppendDataBoundItems="true" Width="200px">
<asp:ListItem Text="-Select User-" Value="0" />
</asp:DropDownList>
<br />
<br />
<br />
<div style="text-align: center;">
<asp:Button runat="server" Font-Size="9pt" Text="Select" CssClass="buttons___" Style="float: left;"
ID="btnSelectPerson" OnClick="btnSelectPerson_Click" />
</div>
</div>
</asp:Panel>
</fieldset>
</div>

ok, so, there was nothing much to do.
have to add this.
protected void btnSelectPerson_Click(object sender, EventArgs e)
{
TextBox t2 = (TextBox)gvProjectResource.FooterRow.FindControl("t2");
t2.Text = ddlPersons.SelectedItem.Text;
mpFindPerson.Hide();
}

How to hide and view ModalPopupExtender?

I am using 4 Modalpopupextender in my start-up page of my project. When I run my start-up page, the panels which I have set under PopupControlID in Modalpopupextender are visible even before the specified TargetControlID is clicked. I have tried to set visible of those to false but it dint helped me and I also tried to create a css class to hide a panel when page is loaded and to view the panel when specified button is clicked but it neither helped me. Please help. Thank you.
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<style type = "text/css">
.hidePanel
{
display:none;
}
.showpanel
{
display : block;
}
.panel
{
background : gray;
padding : 10px;
}
div ul ul
{
display: none;
}
div ul li:hover > ul
{
display: block;
}
div ul li ul:hover > ul
{
display: block;
}
</style>
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager>
<asp:modalpopupextender ID="Modalpopupextender1" CancelControlID = "Button8" TargetControlID = "Button2" PopupControlID = "StaffSP" runat="server"></asp:modalpopupextender>
<asp:modalpopupextender ID="Modalpopupextender2" CancelControlID = "Button10" TargetControlID = "Button3" PopupControlID = "StaffFP" runat="server"></asp:modalpopupextender>
<asp:modalpopupextender ID="Modalpopupextender3" CancelControlID = "Button12" TargetControlID = "Button5" PopupControlID = "AdminSP" runat="server"></asp:modalpopupextender>
<asp:modalpopupextender ID="Modalpopupextender4" CancelControlID = "Button14" TargetControlID = "Button6" PopupControlID = "AdminSP" runat="server"></asp:modalpopupextender>
<asp:Label ID="Label1" runat="server" Font-Bold="True" Font-Names="Arial" Font-Size="XX-Large" Text="Automated Examination System"></asp:Label><br /> <br /><br />
<asp:Panel ID = "Main" runat = "server" Height="181px" Width="275px">
<ul>
<li style="margin-removed 33px; width: 169px;"> <asp:LinkButton ID = "LinkAdmin" runat = "server" onclick="LinkAdmin_Click">Coordinator</asp:LinkButton></li>
<li style="width: 172px; margin-removed 33px"> <asp:LinkButton ID="LinkStaff" runat="server" onclick="LinkStaff_Click">Staff</asp:LinkButton></li>
<li style="margin-removed 33px"> <asp:LinkButton ID = "LinkStudent" runat = "server">Student</asp:LinkButton>
<ul>
<li><asp:LinkButton ID = "LinkButton1" runat = "server">Fresh Registration</asp:LinkButton></li>
<li><asp:LinkButton ID = "LinkButton2" runat = "server">Re Registration</asp:LinkButton></li>
</ul>
</li>
</ul>
</asp:Panel>
</div>
<asp:Panel ID="StaffLogin" runat="server" Height="59px"
style="z-index: 1; left: 302px; top: 112px; position: absolute; height: 59px; width: 275px"
Visible="False" Width="275px">
Staff<br />
<asp:Button ID="Button1" runat="server" Text="Login" />
<asp:Button ID="Button2" runat="server" Text="New Staff" />
<asp:Button ID="Button3" runat="server" Text="Fogot Password" />
</asp:Panel>
<asp:Panel ID="AdminLogin" runat="server"
style="z-index: 1; left: 302px; top: 193px; position: absolute; height: 78px; width: 275px"
Visible="False" Width="275px">
Admin<br />
<asp:Button ID="Button4" runat="server" Text="Login" />
<asp:Button ID="Button5" runat="server" Text="New Admin" />
<asp:Button ID="Button6" runat="server" Text="Forgot Password" />
</asp:Panel>
<asp:Panel ID="StaffSP" runat="server" Height="48px" Width="274px">
Staff SP<br />
<asp:Button ID="Button7" runat="server" Text="Button" />
<asp:Button ID="Button8" runat="server" Text="Cancel" />
</asp:Panel>
<asp:Panel ID="StaffFP" runat="server" Height="48px" Width="274px">
Staff FP<br />
<asp:Button ID="Button9" runat="server" Text="Button" />
<asp:Button ID="Button10" runat="server" Text="Cancel" />
<br />
<br />
</asp:Panel>
<asp:Panel ID="AdminSP" runat="server" Height="48px" Width="274px">
Admin SP<br />
<asp:Button ID="Button11" runat="server" Text="Button" />
<asp:Button ID="Button12" runat="server" Text="Cancel" />
<br />
<br />
</asp:Panel>
<asp:Panel ID="AdminFP" runat="server" Height="48px" Width="274px">
AdminFP<br />
<asp:Button ID="Button13" runat="server" Text="Button" />
<asp:Button ID="Button14" runat="server" Text="Cancel" />
</asp:Panel>
</form>
</body>
</html>
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
public partial class TrailPopup : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void LinkAdmin_Click(object sender, EventArgs e)
{
AdminLogin.Visible = true;
StaffLogin.Visible = false;
}
protected void LinkStaff_Click(object sender, EventArgs e)
{
AdminLogin.Visible = false;
StaffLogin.Visible = true;
}
}
EDIT :
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<style type = "text/css">
.hidePanel
{
display:none;
}
.showpanel
{
display : block;
}
.panel
{
background : gray;
padding : 10px;
}
div ul ul
{
display: none;
}
div ul li:hover > ul
{
display: block;
}
div ul li ul:hover > ul
{
display: block;
}
</style>
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager>
<asp:Label ID="Label1" runat="server" Font-Bold="True" Font-Names="Arial" Font-Size="XX-Large" Text="Automated Examination System"></asp:Label><br /> <br /><br />
<asp:Panel ID = "Main" runat = "server" Height="181px" Width="275px">
<ul>
<li style="margin-left: 33px; width: 169px;"> <asp:LinkButton ID = "LinkAdmin" runat = "server" onclick="LinkAdmin_Click">Coordinator</asp:LinkButton></li>
<li style="width: 172px; margin-left: 33px"> <asp:LinkButton ID="LinkStaff" runat="server" onclick="LinkStaff_Click">Staff</asp:LinkButton></li>
<li style="margin-left: 33px"> <asp:LinkButton ID = "LinkStudent" runat = "server">Student</asp:LinkButton>
<ul>
<li><asp:LinkButton ID = "LinkButton1" runat = "server">Fresh Registration</asp:LinkButton></li>
<li><asp:LinkButton ID = "LinkButton2" runat = "server">Re Registration</asp:LinkButton></li>
</ul>
</li>
</ul>
</asp:Panel>
</div>
<asp:Panel ID="StaffLogin" runat="server" Height="59px"
style="z-index: 1; left: 302px; top: 112px; position: absolute; height: 59px; width: 275px"
Visible="False" Width="275px">
Staff<br />
<asp:Button ID="Button1" runat="server" Text="Login" />
<asp:Button ID="Button2" runat="server" Text="New Staff" />
<asp:Button ID="Button3" runat="server" Text="Fogot Password" />
</asp:Panel>
<asp:Panel ID="AdminLogin" runat="server" style="left: 302px; top: 193px; position: absolute; height: 78px; width: 275px" Visible="False" Width="275px">Admin<br />
<asp:Button ID="Button4" runat="server" Text="Login" />
<asp:Button ID="Button5" runat="server" Text="New Admin" />
<asp:Button ID="Button6" runat="server" Text="Forgot Password" />
</asp:Panel>
<asp:Panel ID="StaffSP" Visible = "false" runat="server" Height="48px" Width="274px">
Staff SP<br />
<asp:modalpopupextender ID="Modalpopupextender1" CancelControlID = "Button8" TargetControlID = "Button2" PopupControlID = "StaffSP" runat="server"></asp:modalpopupextender>
<asp:Button ID="Button7" runat="server" Text="Button" />
<asp:Button ID="Button8" runat="server" Text="Cancel" />
</asp:Panel>
<asp:Panel ID="StaffFP" Visible = "false" runat="server" Height="48px" Width="274px">
Staff FP<br />
<asp:modalpopupextender ID="Modalpopupextender2" CancelControlID = "Button10" TargetControlID = "Button3" PopupControlID = "StaffFP" runat="server"></asp:modalpopupextender>
<asp:Button ID="Button9" runat="server" Text="Button" />
<asp:Button ID="Button10" runat="server" Text="Cancel" />
<br />
<br />
</asp:Panel>
<asp:Panel ID="AdminSP" Visible = "false" runat="server" Height="48px" Width="274px">
Admin SP<br />
<asp:modalpopupextender ID="Modalpopupextender4" CancelControlID = "Button14" TargetControlID = "Button6" PopupControlID = "AdminSP" runat="server"></asp:modalpopupextender>
<asp:Button ID="Button11" runat="server" Text="Button" />
<asp:Button ID="Button12" runat="server" Text="Cancel" />
<br />
<br />
</asp:Panel>
<asp:Panel ID="AdminFP" Visible = "false" runat="server" Height="48px" Width="274px">
AdminFP<br />
<asp:modalpopupextender ID="Modalpopupextender3" CancelControlID = "Button12" TargetControlID = "Button5" PopupControlID = "AdminFP" runat="server"></asp:modalpopupextender>
<asp:Button ID="Button13" runat="server" Text="Button" />
<asp:Button ID="Button14" runat="server" Text="Cancel" />
</asp:Panel>
</form>
</body>
</html>

Call your css class hide panel in every PopupControl used for modalpopupextender control:
`<asp:Panel ID="StaffSP" runat="server" CssClass="hide" Height="48px" Width="274px" >
Staff SP<br />
<asp:Button ID="Button7" runat="server" Text="Button" />
<asp:Button ID="Button8" runat="server" Text="Cancel" />
</asp:Panel>
<asp:Panel ID="StaffFP" runat="server" Height="48px" Width="274px" style="display:none;">
Staff FP<br />
<asp:Button ID="Button9" runat="server" Text="Button" />
<asp:Button ID="Button10" runat="server" Text="Cancel" />
<br />
<br />
</asp:Panel>
<asp:Panel ID="AdminSP" runat="server" Height="48px" Width="274px" CssClass="hidePanel">
Admin SP<br />
<asp:Button ID="Button11" runat="server" Text="Button" />
<asp:Button ID="Button12" runat="server" Text="Cancel" />
<br />
<br />
</asp:Panel>
<asp:Panel ID="AdminFP" runat="server" Height="48px" Width="274px" Visible="false">
AdminFP<br />
<asp:Button ID="Button13" runat="server" Text="Button" />
<asp:Button ID="Button14" runat="server" Text="Cancel" />
</asp:Panel>`

you have put all the 4 TargetControlIDs inside the panels which are not visible

Event not firing in an aspx view page

I have this view in my asp.net application :
<asp:UpdatePanel ID="C_Compte" runat="server" UpdateMode="Conditional">
<ContentTemplate>
Métier:
<asp:TextBox ID="tbAddMetier" CssClass="Textboxes" Width="300px" Height="25px" runat="server"></asp:TextBox>
<asp:Button ID="btnAddMetier" runat="server" Text="Ajouter" CssClass="OffreEmploiSearch" OnClick="Button1_Click" />
<h4 style="font-weight: bold">Mes métiers</h4>
<asp:Repeater ID="rptrMetier" runat="server">
<ItemTemplate>
<div style="font: normal normal normal 14px/1.4em play, sans-serif; color: rgb(95, 94, 93); padding-left: 10px; line-height: 22px">
<strong><%# Eval("Lebelle") %></strong></a>
<asp:ImageButton ID="ImageButton1" runat="server" ImageUrl="~/Design_Ressources/img/attachment.png" OnCommand="ImageButton1_Command" CommandArgument='<%# Eval("Lebelle") %>' />
</div>
</ItemTemplate>
</asp:Repeater>
</ContentTemplate>
</asp:UpdatePanel>
in the code behind
protected void ImageButton1_Command(object sender, CommandEventArgs e)
{
string newjob = e.CommandArgument.ToString().Split(',')[0];
}
Edit Data Binding
protected void Button1_Click(object sender, EventArgs e)
{
string newjob = tbAddMetier.Text;
Metier m = new Metier { Lebelle = newjob };
CurrentCandidat.Metier1.Add(m);
try
{
notrecontexte.SaveChanges();
}
catch
{
}
tbAddMetier.Text = "";
rptrMetier.DataSource = CurrentCandidat.Metier1;
rptrMetier.DataBind();
C_Compte.Update();
}
My problem is that the button clic event is never fired!!
What is the reason?
How can i fix my code?

Add Postback trigger for Button1 as mentioned below :
<asp:UpdatePanel ID="C_Compte" runat="server" UpdateMode="Conditional">
<ContentTemplate>
Métier:
<asp:TextBox ID="tbAddMetier" CssClass="Textboxes" Width="300px" Height="25px" runat="server"></asp:TextBox>
<asp:Button ID="btnAddMetier" runat="server" Text="Ajouter" CssClass="OffreEmploiSearch" OnClick="Button1_Click" />
<h4 style="font-weight: bold">Mes métiers</h4>
<asp:Repeater ID="rptrMetier" runat="server">
<ItemTemplate>
<div style="font: normal normal normal 14px/1.4em play, sans-serif; color: rgb(95, 94, 93); padding-left: 10px; line-height: 22px">
<strong><%# Eval("Lebelle") %></strong></a>
<asp:ImageButton ID="ImageButton1" runat="server" ImageUrl="~/Design_Ressources/img/attachment.png" OnCommand="ImageButton1_Command" CommandArgument='<%# Eval("Lebelle") %>' />
</div>
</ItemTemplate>
</asp:Repeater>
</ContentTemplate>
<Triggers>
<asp:PostBackTrigger ControlID="btnAddMetier"/>
</Triggers>
</asp:UpdatePanel>

Gridview RowCommand not Fire on Server but works Locally

Gridview RowCommand not fire on server but when i use it on local system it works.But when i publish and post to server RowCommand not fired..shall u give me an solution for this...This is my Grid view Code.
Aspx code:
<asp:GridView ID="gvCandiList" runat="server" Style="border: 1px;" RowStyle-BorderColor="#ebf3e4"ViewStateMode="Enabled" RowStyle-BorderStyle="None" GridLines="Both" PageSize="10" AllowPaging="true" AutoGenerateColumns="false" Width="100%" AlternatingRowStyle-BackColor="" CssClass="grdCandList" RowStyle-CssClass="RowStyle" AlternatingRowStyle-CssClass="AltRowStyle" HeaderStyle-CssClass="grdheaderCandList"
DataKeyNames="UserId" OnPageIndexChanging="gvCandiList_PageIndexChanging" OnRowCommand="gvCandiList_RowCommand"OnRowDataBound="gvCandiList_RowDataBound" AllowSorting="true" OnSorting="gvCandiList_Sorting">
<EmptyDataTemplate>
<div class="shadowbox" style="min-height: 75px;">
<br />
<center>
No Data Found.</center>
</div>
</EmptyDataTemplate>
<Columns>
<asp:TemplateField HeaderText="Name" ItemStyle-CssClass="grdcolumncenter" HeaderStyle-CssClass="grdcolumnheadermiddle pad_left5 pad_right5 NameHeaderWidth"
SortExpression="CandiName">
<ItemTemplate>
<h4 style="font-size: 13px; text-align: left; font-weight: normal !important; color: rgb(67, 73, 75);font-family: Calibri;">
<asp:LinkButtonID="lnkCandidateView" runat="server" Style="text-decoration: none;
color: rgb(67, 73, 75);" onmouseover='mouseover(this);' onmouseout='mouseout(this);' CommandName="View" CommandArgument='<%# Eval("CandidateId")%>'>
<asp:Label ToolTip='<%# Eval("CandiName")%>' ID="lblGrdCandiName" runat="server"Text='<%# Eval("CandiName")%>'></asp:Label></asp:LinkButton></h4>
<asp:ImageButton ID="ImageButton1" runat="server" Visible="false" ImageUrl="~/Images/edit.png"CommandName="Modi" CommandArgument='<%# Eval("UserId")%>' ToolTip="Edit" />
<asp:ImageButton ID="ImageButton2" runat="server" ToolTip="View" Visible="false"
ImageUrl="~/Images/view.png" CommandName="View" CommandArgument='<%# Eval("UserId")%>' />
<asp:ImageButton ID="ImageButton3" runat="server" ToolTip="Delete" Visible="false" ImageUrl="~/Images/delete.png" CommandName="Del" CommandArgument='<%# Eval("UserId")%>'
OnClientClick="return confirm('Are you sure ?');" />
<div style="float: left;">
<asp:UpdatePanel ID="UpdatePanel5" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:ImageButton ID="imgbtnNewCmnt" runat="server" Visible="false" CommandName="NewCmnt" CommandArgument='<%# Eval("CandidateId")%>' ToolTip="New Comment" ImageUrl="~/Images/reminder.png" />
</ContentTemplate>
</asp:UpdatePanel>
</div>
</ItemTemplate>
</asp:TemplateField>
</asp:GridView>
ASPX.CS
protected void gvCandiList_RowCommand(object sender, GridViewCommandEventArgs e)
{
if (e.CommandName.Equals("View"))
{
Session["CandiUserId"] = e.CommandArgument.ToString();
DisplayCandidateDetails();
}
}

content is not allowed between opening and closing tags for element "Button"
So replace your lnkCandidateView button with
<asp:Button ID="lnkCandidateView" ToolTip='<%# Eval("CandiName")%>' Text='<%# Eval("CandiName")%>'
runat="server" Style="text-decoration: none; color: rgb(67, 73, 75);" onmouseover='mouseover(this);'
onmouseout='mouseout(this);' CommandName="View" CommandArgument='<%# Eval("CandidateId")%>' />

Seems like a viewState Issue. One solution is to set the EnableViewState property of GridView to true.
You have set ViewStateMode="Enabled" , so Not sure what's the final setting your GridView is inheriting.May be the ContentPlaceHolder of the masterpage has viewstate
turned off. Try turning it on.