Bootstrap实现前端登录页面带验证码功能完整示例

本文实例讲述了Bootstrap实现前端登录页面带验证码功能。分享给大家供大家参考，具体如下：

Bootstrap有自定义的验证码样式，在前端页面可以直接使用，他的css、js在使用前要在开头引入

上代码：

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <!-- 告诉浏览器网页所识别的文件类型及语言类型 -->
  <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
  <title>登录</title>
  <!-- 让一些搜索引擎搜索到你的网页 -->
  <meta name="description" content="">
  <meta name="keywords" content="">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" rel="external nofollow" >
  <script src="https://cdn.bootcss.com/jquery/3.2.1/jquery.min.js"></script>
  <script src="https://cdn.bootcss.com/popper.js/1.12.5/umd/popper.min.js"></script>
  <script src="https://cdn.bootcss.com/bootstrap/4.0.0-beta/js/bootstrap.min.js"></script>
  <script src="tool.js"></script>
  <style>
  .carousel-inner img {
    width:100%;
    height:100%;
  }
  .jumbotron {
    margin-top: 10px;
    margin-bottom: 0px;
    padding-top: 10px;
  }
  #demo {
    width:100%;
    height: 500px;
  }
  .row {
    height: 264px;
  }
  .left {
    float: left;
    width: 70%;
  }
  .right {
    float: left;
    width: 30%;
  }
  .card {
    height: 340px;
  }
  .carousel-inner {
    height: 500px;
  }
  .footer {
    position: absolute;
    bottom: 0;
    height: 60px;
  }
  .jumheight1 {
    height: 100px;
  }
  .jumheight2 {
    height: 100px;
  }
  .end_name {
    margin-bottom: 5px;
  }
  .footer2 {
    padding-top: 210px;
    text-align: center;
  }
  .test{
    margin-bottom: 75px;
  }
  .carousel-control-prev,
  .carousel-control-next{
    bottom: 120px;
  }
  </style>
</head>
<body>
  <div>
    <form class="form active" method="post" action="{:url('index/Login/doLogin')}">
    <div class="jumbotron text-info bg-light jumheight1">
      <h1>图书阅读网</h1>
      <p>一个免费的图书网站</p>
    </div>
    <!-- 轮播图 -->
    <!-- 指示符 -->
    <div class="row">
    <div class="left">
    <div id="demo" class="carousel slide " data-ride="carousel">
      <ul class="carousel-indicators">
        <li data-target="#demo" data-slide-to="0" class="active"></li>
        <li data-target="#demo" data-slide-to="1"></li>
        <li data-target="#demo" data-slide-to="2"></li>
      </ul>
      <!-- 轮播图片 -->
      <div class="carousel-inner">
        <div class="carousel-item active">
          <img src="http://static.runoob.com/images/mix/img_fjords_wide.jpg">
        </div>
        <div class="carousel-item">
          <img src="http://static.runoob.com/images/mix/img_nature_wide.jpg">
        </div>
        <div class="carousel-item">
          <img src="http://static.runoob.com/images/mix/img_mountains_wide.jpg">
        </div>
      </div>
      <!-- 左右切换按钮 -->
      <a href="#demo" rel="external nofollow" rel="external nofollow" class="carousel-control-prev" data-slide="prev">
        <span class="carousel-control-prev-icon"></span>
      </a>
      <a href="#demo" rel="external nofollow" rel="external nofollow" class="carousel-control-next" data-slide=next>
        <span class="carousel-control-next-icon"></span>
      </a>
    </div>
    </div>
    <div class="right">
    <!-- 登陆窗口 -->
    <div class="card">
      <div class="card-header">
        用户登陆
      </div>
      <div class="card-body">
        <form>
          <table style="border-collapse: separate;/*border-spacing: 30px 20px;*/">
            <tr>
              <td class="margin-top:10">
                <label>电话号码：</label>
              </td>
              <td>
                  <input type="text" name="username" pattern="^\d{11}" id="username" class="form-control" placeholder="请输入您的电话号码">
                <!-- <input type="text" name="username" pattern="^\d{11}" id="username" class="form-control" placeholder="请输入您的电话号码" required> -->
              </td>

            </tr>
            <tr>
              <td>
                <label>密码:</label>
              </td>
              <td>
                <input type="password" name="password" id="password" class="form-control" placeholder="请输入您的密码">

              </td>
            </tr>
              <tr>
              <td>
                <label for="captcha" class="test">验证码:</label>
              </td>
              <td> 

                <input type="text" name="captcha" class="form-control "  id="captcha" placeholder="请输入验证码">
                <!-- 点击验证码更换 -->
                <br>
                <div class="code-img"><img height="50px" src="{:captcha_src()}" alt="captcha" onClick="this.src='{:captcha_src()}?'+Math.random()"/></div>
              </td>
            </tr>
          </table>
          <div class="footer">
          <button type="submit" class="btn btn-primary" >登陆</button>
          <button type="submit" class="btn btn-secondary " formaction="{:url('index/Repassword/index')}" >忘记密码？</button>
          </div>
        </form>
      </div>
    </div>
    </div>
    </div>

    </div>
  </div>
  <script>
    fieldTest();
  </script>
</body>
</html>

效果图：

这里还有轮播图，点击验证码时会更新

可以使用在线HTML/CSS/JavaScript代码运行工具：http://tools.jb51.net/code/HtmlJsRun测试上述代码运行效果。

PS：关于bootstrap布局，这里再为大家推荐一款本站的在线可视化布局工具供大家参考使用：

在线bootstrap可视化布局编辑工具：
http://tools.jb51.net/aideddesign/layoutit

希望本文所述对大家基于bootstrap的程序设计有所帮助。