BootStrap——BootStrap练习（栅格系统、组件、插件）

１、头部：主要运用了栅格系统（对于不同的设备应该如何布局来适应屏幕，如何隐藏元素等）

<div class="container">
            <div class="row">
              <div class="col-lg-4 col-md-6 col-sm-6 col-xs-12">
                  <img src="img/top1.jpg" />
              </div>
              <div class="col-lg-4 hidden-md col-sm-6 col-xs-12">
                  <img src="img/top2.jpg" />
              </div>
              <div class="col-lg-4 col-md-6 col-sm-6 col-xs-12" >
                  <a href="#">登录</a>
                  <a href="#">注册</a>
              </div>
            </div>    
</div>

需要先选择容器即“container”，其中主要运用到的是栅格系统的知识，这里用到了两个图片和两个文字链接。

（１）对大屏幕的设置（三部分均分一行）

（２）对中等屏幕的设置（第二个图片被隐藏）

 （３）对小屏幕的设置（两个图片均分一行，两个文字链接独占一行）

 （４）对于超小屏幕（设置为独占一行）

 ２、导航栏

<nav class="navbar-default">
          <div class="container-fluid">
            <!-- Brand and toggle get grouped for better mobile display -->
            <div class="navbar-header">
              <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1" aria-expanded="false">
                <span class="sr-only">Toggle navigation</span>
                <span class="icon-bar"></span>
                <span class="icon-bar"></span>
                <span class="icon-bar"></span>
              </button>
              <a class="navbar-brand" href="#">首页</a>
            </div>
        
            <!-- Collect the nav links, forms, and other content for toggling -->
            <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
              <ul class="nav navbar-nav">
                  <li><a href="#">动物</a></li>
                <li><a href="#">植物 <span class="sr-only">(current)</span></a></li>
                <li><a href="#">微生物</a></li>
                <li class="dropdown">
                  <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">大自然 <span class="caret"></span></a>
                  <ul class="dropdown-menu">
                    <li><a href="#">田野</a></li>
                    <li><a href="#">草原</a></li>
                    <li><a href="#">森林</a></li>
                    <li><a href="#">海洋</a></li>
                    <li><a href="#">湖泊</a></li>
                  </ul>
                </li>
              </ul>
              <form class="navbar-form navbar-left">
                <div class="form-group">
                  <input type="text" class="form-control" placeholder="Search">
                </div>
                <button type="submit" class="btn btn-default">Submit</button>
              </form>
              <ul class="nav navbar-nav navbar-right">
                <li><a href="#">其它</a></li>
                <li class="dropdown">
                  <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">所有分类 <span class="caret"></span></a>
                  <ul class="dropdown-menu">
                    <li><a href="#">动物</a></li>
                    <li><a href="#">植物</a></li>
                    <li><a href="#">微生物</a></li>
                  </ul>
                </li>
              </ul>
            </div><!-- /.navbar-collapse -->
          </div><!-- /.container-fluid -->
        </nav>

有横向导航和下拉菜单，还有搜索框可以搜索自己感兴趣的内容，方便了用户的使用。

３、轮播图

<div class="container-fluid">
            <div id="carousel-example-generic" class="carousel slide" data-ride="carousel">
                <!-- Indicators -->
                <ol class="carousel-indicators">
                    <li data-target="#carousel-example-generic" data-slide-to="0" class="active"></li>
                    <li data-target="#carousel-example-generic" data-slide-to="1"></li>
                    <li data-target="#carousel-example-generic" data-slide-to="2"></li>
                </ol>

                <!-- Wrapper for slides -->
                <div class="carousel-inner" role="listbox">
                    <div class="item active">
                        <img src="img/1.jpg" alt="...">
                        <div class="carousel-caption">
                            ...
                        </div>
                    </div>
                    <div class="item">
                        <img src="img/2.jpg" alt="...">
                        <div class="carousel-caption">
                            ...
                        </div>
                    </div>
                    <div class="item">
                        <img src="img/3.jpg" alt="...">
                        <div class="carousel-caption">
                            ...
                        </div>
                    </div>
                </div>

                <!-- Controls -->
                <a class="left carousel-control" href="#carousel-example-generic" role="button" data-slide="prev">
                    <span class="glyphicon glyphicon-chevron-left" aria-hidden="true"></span>
                    <span class="sr-only">Previous</span>
                </a>
                <a class="right carousel-control" href="#carousel-example-generic" role="button" data-slide="next">
                    <span class="glyphicon glyphicon-chevron-right" aria-hidden="true"></span>
                    <span class="sr-only">Next</span>
                </a>
            </div>
        </div>

 ４、完整代码

<!DOCTYPE html>
<html>
    <head>
        <meta charset="utf-8">
        <!--声明文档兼容模式，表示使用IE浏览器的最新模式-->
        <meta http-equiv="X-UA-Compatible" content="IE=edge">
        <!--设置视口的宽度(值为设备的理想宽度)，页面初始缩放值<理想宽度/可见宽度>-->
        <meta name="viewport" content="width=device-width, initial-scale=1">
        <!-- 上述3个meta标签*必须*放在最前面，任何其他内容都*必须*跟随其后！ -->
        <title>Biology</title>

        <!-- 引入Bootstrap核心样式文件 -->
        <link href="css/bootstrap.css" rel="stylesheet">

        <!-- 引入jQuery核心js文件 -->
        <script src="js/jquery-1.11.3.min.js"></script>
        <!-- 引入BootStrap核心js文件 -->
        <script src="js/bootstrap.min.js"></script>
          <style>
          .carousel-inner img {
              width: 100%;
              height: 100%;
          }
  </style>
    </head>
    <body>
        <!--头部，两张图片、两个文字链接-->
        <div class="container-fluid">
            <div class="row">
              <div class="col-lg-4 col-md-6 col-sm-6 col-xs-12">
                  <img src="img/top1.jpg" />
              </div>
              <div class="col-lg-4 hidden-md col-sm-6 col-xs-12">
                  <img src="img/top2.jpg" />
              </div>
              <div class="col-lg-4 col-md-6 col-sm-6 col-xs-12" >
                  <a href="#">登录</a>
                  <a href="#">注册</a>
              </div>
            </div>    
        </div>
        <!--导航-->
        <nav class="navbar-default">
          <div class="container-fluid">
            <!-- Brand and toggle get grouped for better mobile display -->
            <div class="navbar-header">
              <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1" aria-expanded="false">
                <span class="sr-only">Toggle navigation</span>
                <span class="icon-bar"></span>
                <span class="icon-bar"></span>
                <span class="icon-bar"></span>
              </button>
              <a class="navbar-brand" href="#">首页</a>
            </div>
        
            <!-- Collect the nav links, forms, and other content for toggling -->
            <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
              <ul class="nav navbar-nav">
                  <li><a href="#">动物</a></li>
                <li><a href="#">植物 <span class="sr-only">(current)</span></a></li>
                <li><a href="#">微生物</a></li>
                <li class="dropdown">
                  <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">大自然 <span class="caret"></span></a>
                  <ul class="dropdown-menu">
                    <li><a href="#">田野</a></li>
                    <li><a href="#">草原</a></li>
                    <li><a href="#">森林</a></li>
                    <li><a href="#">海洋</a></li>
                    <li><a href="#">湖泊</a></li>
                  </ul>
                </li>
              </ul>
              <form class="navbar-form navbar-left">
                <div class="form-group">
                  <input type="text" class="form-control" placeholder="Search">
                </div>
                <button type="submit" class="btn btn-default">Submit</button>
              </form>
              <ul class="nav navbar-nav navbar-right">
                <li><a href="#">其它</a></li>
                <li class="dropdown">
                  <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">所有分类 <span class="caret"></span></a>
                  <ul class="dropdown-menu">
                    <li><a href="#">动物</a></li>
                    <li><a href="#">植物</a></li>
                    <li><a href="#">微生物</a></li>
                  </ul>
                </li>
              </ul>
            </div><!-- /.navbar-collapse -->
          </div><!-- /.container-fluid -->
        </nav>
        <!--
            作者：3428834830@qq.com
            时间：2020-01-29
            描述：轮播如（BootStrap组件）
        -->
    
    <div class="container-fluid">
            <div id="carousel-example-generic" class="carousel slide" data-ride="carousel">
                <!-- Indicators -->
                <ol class="carousel-indicators">
                    <li data-target="#carousel-example-generic" data-slide-to="0" class="active"></li>
                    <li data-target="#carousel-example-generic" data-slide-to="1"></li>
                    <li data-target="#carousel-example-generic" data-slide-to="2"></li>
                </ol>

                <!-- Wrapper for slides -->
                <div class="carousel-inner" role="listbox">
                    <div class="item active">
                        <img src="img/1.jpg" alt="...">
                        <div class="carousel-caption">
                            ...
                        </div>
                    </div>
                    <div class="item">
                        <img src="img/2.jpg" alt="...">
                        <div class="carousel-caption">
                            ...
                        </div>
                    </div>
                    <div class="item">
                        <img src="img/3.jpg" alt="...">
                        <div class="carousel-caption">
                            ...
                        </div>
                    </div>
                </div>

                <!-- Controls -->
                <a class="left carousel-control" href="#carousel-example-generic" role="button" data-slide="prev">
                    <span class="glyphicon glyphicon-chevron-left" aria-hidden="true"></span>
                    <span class="sr-only">Previous</span>
                </a>
                <a class="right carousel-control" href="#carousel-example-generic" role="button" data-slide="next">
                    <span class="glyphicon glyphicon-chevron-right" aria-hidden="true"></span>
                    <span class="sr-only">Next</span>
                </a>
            </div>
        </div>
    </body>
</html>