1.运行效果如图所示

bootstrap-基本导航条-带搜索栏_基本


2.实现代码如下

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <title>基本导航条-带搜索栏</title>
    <!-- 最新版本的 Bootstrap 核心 CSS 文件 -->
    <link 
    rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" 
    integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" 
    crossorigin="anonymous">

    <!-- 可选的 Bootstrap 主题文件(一般不用引入) -->
    <link rel="stylesheet" 
    href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap-theme.min.css" 
    integrity="sha384-rHyoN1iRsVXV4nD0JutlnGaslCJuC7uwjduW9SVrLvRYooPp2bWYgmgJQIXwl/Sp" 
    crossorigin="anonymous">
</head>
<body>
    <div class="navbar navbar-default" role="navigation">
       <div class="navbar-header">
           <a href="##" class="navbar-brand">xx网</a>
       </div>
        <ul class="nav navbar-nav">
            <li class="active"><a href="##">网站首页</a></li>
              <li class="dropdown">
                <a href="##" data-toggle="dropdown" class="dropdown-toggle">系列教程
                <span class="caret"></span></a>
                <ul class="dropdown-menu">
                    <li><a href="##">CSS3</a></li>
                    <li><a href="##">JavaScript</a></li>
                    <li class="disabled"><a href="##">PHP</a></li>
                </ul>
             </li>
              <li><a href="##">名师介绍</a></li>
              <li><a href="##">成功案例</a></li>
              <li><a href="##">关于我们</a></li>
        </ul>
          <form action="##" class="navbar-form navbar-left" rol="search">
               <div class="form-group">
                   <input type="text" class="form-control" placeholder="请输入关键词" />
               </div>
            <button type="submit" class="btn btn-default">搜索</button>
           </form>
    </div>


    <script src="https://cdn.bootcss.com/jquery/3.2.1/jquery.min.js"></script>
    <!-- 最新的 Bootstrap 核心 JavaScript 文件 -->
    <script src="https://cdn.bootcss.com/bootstrap/3.3.7/js/bootstrap.min.js" 
    integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" 
    crossorigin="anonymous"></script>
</body>
</html>