Hi akhter,
Code is working in master page. Refer thc code.
HTML
MasterPage
<%@ Master Language="C#" AutoEventWireup="true" CodeFile="MasterPage.master.cs" Inherits="MasterPage" %>
<!DOCTYPE html>
<html>
<head runat="server">
<title></title>
<asp:ContentPlaceHolder ID="head" runat="server">
</asp:ContentPlaceHolder>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
<style type="text/css">
body {
margin: 0;
font-family: Arial
}
.topnav {
overflow: hidden;
background-color: #333;
}
.topnav a {
float: left;
display: block;
color: #f2f2f2;
text-align: center;
padding: 14px 16px;
text-decoration: none;
font-size: 17px;
}
.active {
background-color: #04AA6D;
color: white;
}
.topnav .icon {
display: none;
}
.dropdown {
float: left;
overflow: hidden;
}
.dropdown .dropbtn {
font-size: 17px;
border: none;
outline: none;
color: white;
padding: 14px 16px;
background-color: black;
font-family: inherit;
margin: 0;
}
.dropdown-content {
display: none;
position: absolute;
background-color: #f9f9f9;
min-width: 160px;
box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
z-index: 1;
}
.dropdown-content a {
float: none;
color: black;
padding: 12px 16px;
text-decoration: none;
display: block;
text-align: left;
}
.topnav a:hover, .dropdown:hover .dropbtn {
background-color: #555;
color: white;
cursor:pointer;
}
.dropdown-content a:hover {
background-color: #ddd;
color: black;
}
.dropdown:hover .dropdown-content {
display: block;
}
@media screen and (max-width: 600px) {
.topnav a:not(:first-child), .dropdown .dropbtn {
display: none;
}
.topnav a.icon {
float: right;
display: block;
}
}
@media screen and (max-width: 600px) {
.topnav.responsive {
position: relative;
}
.topnav.responsive .icon {
position: absolute;
right: 0;
top: 0;
}
.topnav.responsive a {
float: none;
display: block;
text-align: left;
}
.topnav.responsive .dropdown {
float: none;
}
.topnav.responsive .dropdown-content {
position: relative;
}
.topnav.responsive .dropdown .dropbtn {
display: block;
width: 100%;
text-align: left;
}
}
</style>
</head>
<body>
<form id="form1" runat="server">
<div class="topnav" id="myTopnav">
<a href="#home" class="active">Home</a>
<div class="dropdown">
<button class="dropbtn">
Dropdown
<i class="fa fa-caret-down"></i>
</button>
<div class="dropdown-content">
<a href="/COA">COA</a>
<a href="/Onlinerecpt">Online Form</a>
<a href="/chqrecpt">Cheque Form</a>
<a href="/invrt">General Inward Form</a>
<a href="/genpay">General Payment Form</a>
<a href="/transdetail">Online Details</a>
<a href="/chqDetail">Cheque Status</a>
<a href="/ledger1">Ledger</a>
<a href="/hecinv2">Invoice</a>
<a href="/HecoDutyFrm">Duty</a>
</div>
</div>
<a href="javascript:void(0);" style="font-size: 15px;" class="icon" onclick="OpenClose()">☰</a>
</div>
<script>
function OpenClose() {
var x = document.getElementById("myTopnav");
if (x.className === "topnav") {
x.className += " responsive";
} else {
x.className = "topnav";
}
}
</script>
<div class="container body-content">
<asp:ContentPlaceHolder ID="ContentPlaceHolder1" runat="server">
</asp:ContentPlaceHolder>
<hr />
<footer>
<p>© <%: DateTime.Now.Year %> - My ASP.NET Application</p>
</footer>
</div>
</form>
</body>
</html>
Default
<%@ Page Title="" Language="C#" MasterPageFile="~/MasterPage.master" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" Runat="Server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server">
</asp:Content>
Screenshot
