详解bootstrap导航栏.nav与.navbar区别

刚刚看了bootstrap的导航栏，发现有点弄混了，现在来整理一下；

导航栏是一个很好的功能，是 Bootstrap 网站的一个突出特点。导航栏在您的应用或网站中作为导航页头的响应式基础组件。导航栏在移动设备的视图中是折叠的，随着可用视口宽度的增加，导航栏也会水平展开。在 Bootstrap 导航栏的核心中，导航栏包括了站点名称和基本的导航定义样式。

一、简单的ul,li组成的导航：

<ul class=\"nav nav-pills justify-content-center bg-dark nav-dark\">
    <li class=\"nav-item\">
      <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"nav-link\">1</a>
    </li>
    <li class=\"nav-item\">
      <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"nav-link\">2</a>
    </li>
    <li class=\"nav-item\">
      <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"nav-link\">3</a>
    </li>
  </ul>

 

//解析：.nav .nav-item .nav-link表示ul li是导航——.nav-pills表示胶囊状导航——.bg-dark/.nav-dark表示黑底白字——.justify-content-center表示导航栏在浏览器上居中显示

在浏览器上显示为：

缩小浏览器窗口显示为：

二、导航栏——<nav>标签中class=\”navbar navbar-expand-sm\”——<ul>中class=\”navbar-nav\”——<li>中class=\”nav-item\”

代码为：

<nav class=\"navbar navbar-expand-sm bg-dark navbar-dark\">
  <ul class=\"navbar-nav\">
    <li class=\"nav-item active\">
      <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"nav-link\">link1</a>
    </li>
    <li class=\"nav-item\">
      <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"nav-link\">link1</a>
    </li>
    <li class=\"nav-item\">
      <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"nav-link\">link1</a>
    </li>
    <li class=\"nav-item\">
      <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"nav-link\">link1</a>
    </li>  
  </ul>
</nav>

正常窗口显示为：

 缩小窗口小于576px时： 

三、折叠导航栏

当窗口小于576px的时候，不仅仅是简单的编程垂直导航；显示为一个button按钮，导航链接隐藏，点击button显示；

 代码为：

<nav class=\"navbar navbar-expand-sm bg-dark navbar-dark fixed-top\">
  <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"navbar-brand\">
      <img src=\"\" alt=\"logo\" style=\"width:70px;height:30px;\">
  </a>
  <button class=\"navbar-toggler\" type=\"button\" data-toggle=\"collapse\" data-target=\"#collapsible\">
    <span class=\"navbar-toggler-icon\"></span>
  </button>
  <div class=\"collapse navbar-collapse\" id=\"collapsible\">
  <ul class=\"navbar-nav\">
    <li class=\"nav-item active\">
      <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"nav-link\">link1</a>
    </li>
    <li class=\"nav-item\">
      <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"nav-link\">link1</a>
    </li>
    <li class=\"nav-item\">
      <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"nav-link\">link1</a>
    </li>
    <li class=\"nav-item\">
      <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"nav-link\">link1</a>
    </li>  
  </ul>
  
</nav>

 //注意：.navbar-brand是品牌logo；

窗口大于576的时候，显示为：

窗口小于576的时候，显示为：

四、导航栏加上form表单表示搜索框：【？？？？？】

代码如下：

<nav class=\"navbar navbar-expand-sm bg-dark navbar-dark fixed-top\">
  <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"navbar-brand\">
      <img src=\"\" alt=\"logo\" style=\"width:70px;height:30px;\">
  </a>
  <button class=\"navbar-toggler\" type=\"button\" data-toggle=\"collapse\" data-target=\"#collapsible\">
    <span class=\"navbar-toggler-icon\"></span>
  </button>
  <div class=\"collapse navbar-collapse\" id=\"collapsible\">
  <ul class=\"navbar-nav\">
    <li class=\"nav-item active\">
      <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"nav-link\">link1</a>
    </li>
    <li class=\"nav-item\">
      <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"nav-link\">link1</a>
    </li>
    <li class=\"nav-item\">
      <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"nav-link\">link1</a>
    </li>
    <li class=\"nav-item\">
      <a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" class=\"nav-link\">link1</a>
    </li>  
  </ul>
  <form class=\"form-inline\">
        <div class=\"input-group\">
          <span class=\"input-group-addon\">@</span>
          <input list=\"dl\" type=\"text\" class=\"form-control\" placeholder=\"Search\"/>
          <datalist id=\"dl\">
            <option value=\"IE\"></option>
            <option value=\"Firefox\"></option>
            <option value=\"chrome\"></option>
            <option value=\"safari\"></option>
          </datalist>
        </div>
        
        <button class=\"btn btn-success\" type=\"submit\">search</button>
      </form>
</nav>

如图所示，如何使得导航栏中的form表单右对齐，移到最右边？？？？？float：eight应该也行吧。。

emmmm…..知道了上面的解决方法了：利用网格系统，将左边的ul,li和右边的form表单分别排列；.col-sm-6;然后再给form表单右浮动；

代码如下：

<div class=\"container-fluid\">
  <div class=\"row\">
    <!-- 导航栏 -->
    <nav class=\"navbar fixed-top navbar-expand-sm bg-dark navbar-dark\">
      <div class=\"col-lg-4\">
      <ul class=\"navbar-nav\">
        <li class=\"nav-item\">
          <a class=\"nav-link\" href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" >link1</a>
        </li>
        <li class=\"nav-item\">
          <a class=\"nav-link\" href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" >link2</a>
        </li>
        <li class=\"nav-item\">
          <a class=\"nav-link\" href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" rel=\"external nofollow\" >link3</a>
        </li>
      </ul>
      </div>
<!-- 导航栏表单与按钮 -->
    <div class=\"col-lg-8\">
      <form class=\"form-inline\" style=\"float:right;\">
        <div class=\"input-group\">
          <span class=\"input-group-addon\">@</span>
          <input list=\"dl\" type=\"text\" class=\"form-control\" placeholder=\"Search\"/>
          <datalist id=\"dl\">
            <option value=\"IE\"></option>
            <option value=\"Firefox\"></option>
            <option value=\"chrome\"></option>
            <option value=\"safari\"></option>
          </datalist>
          <button class=\"btn btn-success\" type=\"submit\">search</button>
        </div>              
      </form>
      </div>      
    </nav>
    </div>
      </div>

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。