直接上代码：
解释在注释部分，注意想让模态框显示或不显示，只需控制黄色部分class中的show
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>BootStrapDemo</title>
<!--支持移动设备有限-->
<meta name="viewport" content="width=device-width,initial-scale=1"/>
<link rel="stylesheet" href="css/bootstrap.css" />
<script type="text/javascript" src="js/jquery-1.4.2.js"></script>
<script type="text/javascript" src="js/bootstrap.js"></script>
</head>
<body>
<div class="container">
<!--模态框开始-->
<div class="modal" id="myModal">
<div class="modal-dialog">
<div class="modal-content">
<!--模态框头-->
<div class="modal-header">
<button class="close" data-dismiss="modal" id="close">×</button>
<h4 class="modal-title">标题信息</h4>
</div>
<!--模态框体-->
<div class="modal-body">
<form class="form-horizontal">
<div class="form-group">
<label for="inputEmail3" class="col-sm-2 control-label">Email</label>
<div class="col-sm-10">
<input type="email" class="form-control" id="inputEmail3" placeholder="Email">
</div>
</div>
<div class="form-group">
<label for="inputPassword3" class="col-sm-2 control-label">Password</label>
<div class="col-sm-10">
<input type="password" class="form-control" id="inputPassword3" placeholder="Password">
</div>
</div>
<div class="form-group">
<div class="col-sm-offset-2 col-sm-10">
<div class="checkbox">
<label>
<input type="checkbox"> Remember me
</label>
</div>
</div>
</div>
<div class="form-group">
<div class="col-sm-offset-2 col-sm-10">
<button type="submit" class="btn btn-default">Sign in</button>
</div>
</div>
</form>
</div>
<!--模态框脚-->
<div class="modal-footer">
<button class="btn btn-default">取消</button>
<button class="btn btn-primary">确定</button>
</div>
</div>
</div>
</div>
<button class="btn btn-primary" data-toggle="modal" data-target="#myModal" id="btn">显示我的模态框</button>
</div>
<!--javascript控制模态框的class，从而控制显示与关闭，和表单提交-->
<script type="text/javascript">
var modelClass = $("#myModal").attr("class");
$("#btn").click(function(){
$("#myModal").addClass("show");
});
$("#close").click(function(){
$("#myModal").removeClass("show");
});
</script>
</body>
</html>