我想在用户尝试重新加载页面时显示一个确认框.我在我的项目中尝试过它并没有用.我已经创建了一个我尝试过的示例代码,即使它不起作用.任何人都可以告诉我哪里出错了.我甚至没有收到确认框.我使用的是Chrome 33+.我需要在弹出框之前在window.onbeforeunload中执行一些代码.
<!DOCTYPE>
<html>
<body>
<script type="text/javascript">
window.onbeforeunload = function()
{
var r = confirm("Are you sure you want to reload the page.");
if(r)
{
window.location.reload();
}
else
{
}
};
</script>
</body>
</html>
Run Code Online (Sandbox Code Playgroud) 我正在使用navbar
该类作为导航菜单。当我使用该类时navbar-fixed-top
,正文中的一些内容被隐藏在导航栏后面。任何机构都可以告诉我为什么会发生这种情况吗?
下面是我一直在研究的代码。
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>JanaSena Party</title>
<!-- Bootstrap -->
<link href="bootstrap/css/bootstrap.min.css" rel="stylesheet">
</head>
<body style = "background-color: lightgrey;">
<div class = "navbar navbar-default navbar-fixed-top">
<div class = "container">
<div class = "navbar-header ">
<a href = "#" class = "navbar-brand pull-left">BRAND</a>
<button class = "navbar-toggle pull-right" data-toggle = "collapse" data-target = ".navHeaderCollapse">
<span class = "icon-bar"></span>
<span class = "icon-bar"></span>
<span class = "icon-bar"></span> …
Run Code Online (Sandbox Code Playgroud) 我使用bootstrap网站上的示例代码创建了一个进度条.我在进度条的开头有一个间隙,我无法将其删除.我已附上图片以显示它的外观.
这是代码,
<div class = "form-group">
<div class = "col-xs-12">
<h4>In Progress</h4>
</div>
<div class="progress progress-striped active col-xs-12">
<div class="progress-bar col-xs-12" role="progressbar" aria-valuenow="45" aria-valuemin="0" aria-valuemax="100" style="width: 45%; margin-left: 0; margin-right: 0; padding: 0px 0px 0px 0px">
<span class="sr-only">45% Complete</span>
</div>
</div>
<div class = "col-xs-12">
<button class = "btn btn-danger col-xs-6 pull-right">Stop</button>
</div>
</div>
Run Code Online (Sandbox Code Playgroud) css progress twitter-bootstrap progress-bar twitter-bootstrap-3
我正在初始化一个char
带有一些随机值的指针,当我试图删除它时,我无法做到.这是为什么?
这是我在做的事情:
int main()
{
char *s = new char[50]; /*
* I know there is no reason for
* using new if initializing, but
* in order to use delete we need
* to allocate using new.
*/
s = "Harry";
delete s;
return 0;
}
Run Code Online (Sandbox Code Playgroud)