密码框的点击眼睛的显示与隐藏，图标引用是bootstrap中的fontawesome
（复制整个 font-awesome 文件夹到您的项目中）
还需要引入
  <link rel="stylesheet" type="text/css" href="bootstrap.min.css">
  <link rel="stylesheet" type="text/css" href="Font-Awesome/css/font-awesome.min.css">
<!doctype html>
<html>
	<head>
			<meta charset="utf-8">
			<title>密码框</title>
			<link rel="stylesheet" type="text/css" href="bootstrap.min.css">
			<link rel="stylesheet" type="text/css" href="Font-Awesome/css/font-awesome.min.css">
	</head>
<body>
    <div class="content">
        <div class="input_block">
            <i class="fa fa-eye" onclick="hideShowPsw()" id="eye"></i>
            <input type="password" id="password" placeholder="密码"/>
        </div>
    </div>
   <script type="text/javascript">
			var eye = document.getElementById("eye");
			var password = document.getElementById("password");
			//隐藏text block，显示password block
			function hideShowPsw(){
					if (password.type == "password") {
							password.type = "text";
							eye.className='fa fa-eye-slash'
					}else {
							password.type = "password";
							eye.className='fa fa-eye'
					}
				}
	</script>
</body>
</html>