嗨，我正在研究一些引导带功能，并且轮播元素存在一些问题。
我正在尝试使用此示例-> https://getbootstrap.com/docs/4.5/examples/carousel/
并且我遇到的问题是我的代码带有轮播，但是蓝色按钮上方的文本没有显示出来...What my page looks like
这是我的代码（仅复制了示例）我认为问题一定出在我的CSS或引导文件中
<!DOCTYPE html>
<html lang="en">
<!--You do not see what is in the head-->
<head>
<meta charset="utf-8">
<!-- Bootstrap -->
<link href="css/bootstrap.css" rel="stylesheet">
<link href="main.css" rel="stylesheet" type="text/css">
<link href="css/basic-template.css" rel="stylesheet">
<!-- HTML5 shim and Respond.js for IE8 support of HTML5 elements and media queries -->
<!-- WARNING: Respond.js doesn't work if you view the page via file:// -->
<!--[if lt IE 9]>
<script src="https://oss.maxcdn.com/html5shiv/3.7.2/html5shiv.min.js"></script>
<script src="https://oss.maxcdn.com/respond/1.4.2/respond.min.js"></script>
<![endif]-->
<!--Fav icon-->
<link href="#" rel="favicon"/> <!--Example link (images/favicon.png)-->
<!--Title of page-->
<title>Title - Home</title>
</head>
<body>
<header>
<nav class="navbar navbar-expand-md navbar-dark fixed-top bg-dark">
<a class="navbar-brand" href="#">Carousel</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarCollapse" aria-controls="navbarCollapse" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarCollapse">
<ul class="navbar-nav mr-auto">
<li class="nav-item active">
<a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Link</a>
</li>
<li class="nav-item">
<a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
</li>
</ul>
<form class="form-inline mt-2 mt-md-0">
<input class="form-control mr-sm-2" type="text" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
</form>
</div>
</nav>
</header>
<main role="main">
<div id="myCarousel" class="carousel slide" data-ride="carousel">
<ol class="carousel-indicators">
<li data-target="#myCarousel" data-slide-to="0" class=""></li>
<li data-target="#myCarousel" data-slide-to="1" class="active"></li>
<li data-target="#myCarousel" data-slide-to="2" class=""></li>
</ol>
<div class="carousel-inner">
<div class="carousel-item">
<svg class="bd-placeholder-img" width="100%" height="100%" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img"><rect width="100%" height="100%" fill="#777"></rect></svg>
<div class="container">
<div class="carousel-caption text-left">
<h1>Example headline.</h1>
<p>Cras justo odio, dapibus ac facilisis in, egestas eget quam. Donec id elit non mi porta gravida at eget metus. Nullam id dolor id nibh ultricies vehicula ut id elit.</p>
<p><a class="btn btn-lg btn-primary" href="#" role="button">Sign up today</a></p>
</div>
</div>
</div>
<div class="carousel-item active">
<svg class="bd-placeholder-img" width="100%" height="100%" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img"><rect width="100%" height="100%" fill="#777"></rect></svg>
<div class="container">
<div class="carousel-caption">
<h1>Another example headline.</h1>
<p>Cras justo odio, dapibus ac facilisis in, egestas eget quam. Donec id elit non mi porta gravida at eget metus. Nullam id dolor id nibh ultricies vehicula ut id elit.</p>
<p><a class="btn btn-lg btn-primary" href="#" role="button">Learn more</a></p>
</div>
</div>
</div>
<div class="carousel-item">
<svg class="bd-placeholder-img" width="100%" height="100%" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img"><rect width="100%" height="100%" fill="#777"></rect></svg>
<div class="container">
<div class="carousel-caption text-right">
<h1>One more for good measure.</h1>
<p>Cras justo odio, dapibus ac facilisis in, egestas eget quam. Donec id elit non mi porta gravida at eget metus. Nullam id dolor id nibh ultricies vehicula ut id elit.</p>
<p><a class="btn btn-lg btn-primary" href="#" role="button">Browse gallery</a></p>
</div>
</div>
</div>
</div>
<a class="carousel-control-prev" href="#myCarousel" role="button" data-slide="prev">
<span class="carousel-control-prev-icon" aria-hidden="true"></span>
<span class="sr-only">Previous</span>
</a>
<a class="carousel-control-next" href="#myCarousel" role="button" data-slide="next">
<span class="carousel-control-next-icon" aria-hidden="true"></span>
<span class="sr-only">Next</span>
</a>
</div>
<!-- Marketing messaging and featurettes
================================================== -->
<!-- Wrap the rest of the page in another container to center all the content. -->
<div class="container marketing">
<!-- Three columns of text below the carousel -->
<div class="row">
<div class="col-lg-4">
<svg class="bd-placeholder-img rounded-circle" width="140" height="140" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img" aria-label="Placeholder: 140x140"><title>Placeholder</title><rect width="100%" height="100%" fill="#777"></rect><text x="50%" y="50%" fill="#777" dy=".3em">140x140</text></svg>
<h2>Heading</h2>
<p>Donec sed odio dui. Etiam porta sem malesuada magna mollis euismod. Nullam id dolor id nibh ultricies vehicula ut id elit. Morbi leo risus, porta ac consectetur ac, vestibulum at eros. Praesent commodo cursus magna.</p>
<p><a class="btn btn-secondary" href="#" role="button">View details »</a></p>
</div><!-- /.col-lg-4 -->
<div class="col-lg-4">
<svg class="bd-placeholder-img rounded-circle" width="140" height="140" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img" aria-label="Placeholder: 140x140"><title>Placeholder</title><rect width="100%" height="100%" fill="#777"></rect><text x="50%" y="50%" fill="#777" dy=".3em">140x140</text></svg>
<h2>Heading</h2>
<p>Duis mollis, est non commodo luctus, nisi erat porttitor ligula, eget lacinia odio sem nec elit. Cras mattis consectetur purus sit amet fermentum. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh.</p>
<p><a class="btn btn-secondary" href="#" role="button">View details »</a></p>
</div><!-- /.col-lg-4 -->
<div class="col-lg-4">
<svg class="bd-placeholder-img rounded-circle" width="140" height="140" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img" aria-label="Placeholder: 140x140"><title>Placeholder</title><rect width="100%" height="100%" fill="#777"></rect><text x="50%" y="50%" fill="#777" dy=".3em">140x140</text></svg>
<h2>Heading</h2>
<p>Donec sed odio dui. Cras justo odio, dapibus ac facilisis in, egestas eget quam. Vestibulum id ligula porta felis euismod semper. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus.</p>
<p><a class="btn btn-secondary" href="#" role="button">View details »</a></p>
</div><!-- /.col-lg-4 -->
</div><!-- /.row -->
<!-- START THE FEATURETTES -->
<hr class="featurette-divider">
<div class="row featurette">
<div class="col-md-7">
<h2 class="featurette-heading">First featurette heading. <span class="text-muted">It’ll blow your mind.</span></h2>
<p class="lead">Donec ullamcorper nulla non metus auctor fringilla. Vestibulum id ligula porta felis euismod semper. Praesent commodo cursus magna, vel scelerisque nisl consectetur. Fusce dapibus, tellus ac cursus commodo.</p>
</div>
<div class="col-md-5">
<svg class="bd-placeholder-img bd-placeholder-img-lg featurette-image img-fluid mx-auto" width="500" height="500" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img" aria-label="Placeholder: 500x500"><title>Placeholder</title><rect width="100%" height="100%" fill="#eee"></rect><text x="50%" y="50%" fill="#aaa" dy=".3em">500x500</text></svg>
</div>
</div>
<hr class="featurette-divider">
<div class="row featurette">
<div class="col-md-7 order-md-2">
<h2 class="featurette-heading">Oh yeah, it’s that good. <span class="text-muted">See for yourself.</span></h2>
<p class="lead">Donec ullamcorper nulla non metus auctor fringilla. Vestibulum id ligula porta felis euismod semper. Praesent commodo cursus magna, vel scelerisque nisl consectetur. Fusce dapibus, tellus ac cursus commodo.</p>
</div>
<div class="col-md-5 order-md-1">
<svg class="bd-placeholder-img bd-placeholder-img-lg featurette-image img-fluid mx-auto" width="500" height="500" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img" aria-label="Placeholder: 500x500"><title>Placeholder</title><rect width="100%" height="100%" fill="#eee"></rect><text x="50%" y="50%" fill="#aaa" dy=".3em">500x500</text></svg>
</div>
</div>
<hr class="featurette-divider">
<div class="row featurette">
<div class="col-md-7">
<h2 class="featurette-heading">And lastly, this one. <span class="text-muted">Checkmate.</span></h2>
<p class="lead">Donec ullamcorper nulla non metus auctor fringilla. Vestibulum id ligula porta felis euismod semper. Praesent commodo cursus magna, vel scelerisque nisl consectetur. Fusce dapibus, tellus ac cursus commodo.</p>
</div>
<div class="col-md-5">
<svg class="bd-placeholder-img bd-placeholder-img-lg featurette-image img-fluid mx-auto" width="500" height="500" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img" aria-label="Placeholder: 500x500"><title>Placeholder</title><rect width="100%" height="100%" fill="#eee"></rect><text x="50%" y="50%" fill="#aaa" dy=".3em">500x500</text></svg>
</div>
</div>
<hr class="featurette-divider">
<!-- /END THE FEATURETTES -->
</div><!-- /.container -->
<!-- FOOTER -->
<footer class="container">
<p class="float-right"><a href="#">Back to top</a></p>
<p>© 2017-2020 Company, Inc. · <a href="#">Privacy</a> · <a href="#">Terms</a></p>
</footer>
</main>
<script src="https://code.jquery.com/jquery-3.5.1.slim.min.js" integrity="sha384-DfXdz2htPH0lsSSs5nCTpuj/zy4C+OGpamoFVy38MVBnE+IbbVYUew+OrCXaRkfj" crossorigin="anonymous"></script>
<script>window.jQuery || document.write('<script src="/docs/4.5/assets/js/vendor/jquery.slim.min.js"><\/script>')</script><script src="/docs/4.5/dist/js/bootstrap.bundle.min.js" integrity="sha384-1CmrxMRARb6aLqgBO7yyAxTOQE2AKb9GfXnEo760AUcUmFx3ibVJJAzGytlQcNXd" crossorigin="anonymous"></script>
</body>
</html>您的代码中缺少轮播CSS。
<link href="https://getbootstrap.com/docs/4.5/examples/carousel/carousel.css" rel="stylesheet">
这有助于设置转盘项目的高度。
.carousel-item {
height: 32rem;
}
<!DOCTYPE html>
<html lang="en">
<!--You do not see what is in the head-->
<head>
<meta charset="utf-8">
<!-- Bootstrap -->
<link href="https://getbootstrap.com/docs/4.5/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-9aIt2nRpC12Uk9gS9baDl411NQApFmC26EwAOH8WgZl5MYYxFfc+NcPb1dKGj7Sk" crossorigin="anonymous">
<link href="main.css" rel="stylesheet" type="text/css">
<link href="css/basic-template.css" rel="stylesheet">
<link href="https://getbootstrap.com/docs/4.5/examples/carousel/carousel.css" rel="stylesheet">
<!-- HTML5 shim and Respond.js for IE8 support of HTML5 elements and media queries -->
<!-- WARNING: Respond.js doesn't work if you view the page via file:// -->
<!--[if lt IE 9]>
<script src="https://oss.maxcdn.com/html5shiv/3.7.2/html5shiv.min.js"></script>
<script src="https://oss.maxcdn.com/respond/1.4.2/respond.min.js"></script>
<![endif]-->
<!--Fav icon-->
<link href="#" rel="favicon"/> <!--Example link (images/favicon.png)-->
<!--Title of page-->
<title>Title - Home</title>
</head>
<body>
<header>
<nav class="navbar navbar-expand-md navbar-dark fixed-top bg-dark">
<a class="navbar-brand" href="#">Carousel</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarCollapse" aria-controls="navbarCollapse" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarCollapse">
<ul class="navbar-nav mr-auto">
<li class="nav-item active">
<a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Link</a>
</li>
<li class="nav-item">
<a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
</li>
</ul>
<form class="form-inline mt-2 mt-md-0">
<input class="form-control mr-sm-2" type="text" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
</form>
</div>
</nav>
</header>
<main role="main">
<div id="myCarousel" class="carousel slide" data-ride="carousel">
<ol class="carousel-indicators">
<li data-target="#myCarousel" data-slide-to="0" class=""></li>
<li data-target="#myCarousel" data-slide-to="1" class="active"></li>
<li data-target="#myCarousel" data-slide-to="2" class=""></li>
</ol>
<div class="carousel-inner">
<div class="carousel-item">
<svg class="bd-placeholder-img" width="100%" height="100%" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img"><rect width="100%" height="100%" fill="#777"></rect></svg>
<div class="container">
<div class="carousel-caption text-left">
<h1>Example headline.</h1>
<p>Cras justo odio, dapibus ac facilisis in, egestas eget quam. Donec id elit non mi porta gravida at eget metus. Nullam id dolor id nibh ultricies vehicula ut id elit.</p>
<p><a class="btn btn-lg btn-primary" href="#" role="button">Sign up today</a></p>
</div>
</div>
</div>
<div class="carousel-item active">
<svg class="bd-placeholder-img" width="100%" height="100%" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img"><rect width="100%" height="100%" fill="#777"></rect></svg>
<div class="container">
<div class="carousel-caption">
<h1>Another example headline.</h1>
<p>Cras justo odio, dapibus ac facilisis in, egestas eget quam. Donec id elit non mi porta gravida at eget metus. Nullam id dolor id nibh ultricies vehicula ut id elit.</p>
<p><a class="btn btn-lg btn-primary" href="#" role="button">Learn more</a></p>
</div>
</div>
</div>
<div class="carousel-item">
<svg class="bd-placeholder-img" width="100%" height="100%" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img"><rect width="100%" height="100%" fill="#777"></rect></svg>
<div class="container">
<div class="carousel-caption text-right">
<h1>One more for good measure.</h1>
<p>Cras justo odio, dapibus ac facilisis in, egestas eget quam. Donec id elit non mi porta gravida at eget metus. Nullam id dolor id nibh ultricies vehicula ut id elit.</p>
<p><a class="btn btn-lg btn-primary" href="#" role="button">Browse gallery</a></p>
</div>
</div>
</div>
</div>
<a class="carousel-control-prev" href="#myCarousel" role="button" data-slide="prev">
<span class="carousel-control-prev-icon" aria-hidden="true"></span>
<span class="sr-only">Previous</span>
</a>
<a class="carousel-control-next" href="#myCarousel" role="button" data-slide="next">
<span class="carousel-control-next-icon" aria-hidden="true"></span>
<span class="sr-only">Next</span>
</a>
</div>
<!-- Marketing messaging and featurettes
================================================== -->
<!-- Wrap the rest of the page in another container to center all the content. -->
<div class="container marketing">
<!-- Three columns of text below the carousel -->
<div class="row">
<div class="col-lg-4">
<svg class="bd-placeholder-img rounded-circle" width="140" height="140" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img" aria-label="Placeholder: 140x140"><title>Placeholder</title><rect width="100%" height="100%" fill="#777"></rect><text x="50%" y="50%" fill="#777" dy=".3em">140x140</text></svg>
<h2>Heading</h2>
<p>Donec sed odio dui. Etiam porta sem malesuada magna mollis euismod. Nullam id dolor id nibh ultricies vehicula ut id elit. Morbi leo risus, porta ac consectetur ac, vestibulum at eros. Praesent commodo cursus magna.</p>
<p><a class="btn btn-secondary" href="#" role="button">View details »</a></p>
</div><!-- /.col-lg-4 -->
<div class="col-lg-4">
<svg class="bd-placeholder-img rounded-circle" width="140" height="140" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img" aria-label="Placeholder: 140x140"><title>Placeholder</title><rect width="100%" height="100%" fill="#777"></rect><text x="50%" y="50%" fill="#777" dy=".3em">140x140</text></svg>
<h2>Heading</h2>
<p>Duis mollis, est non commodo luctus, nisi erat porttitor ligula, eget lacinia odio sem nec elit. Cras mattis consectetur purus sit amet fermentum. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh.</p>
<p><a class="btn btn-secondary" href="#" role="button">View details »</a></p>
</div><!-- /.col-lg-4 -->
<div class="col-lg-4">
<svg class="bd-placeholder-img rounded-circle" width="140" height="140" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img" aria-label="Placeholder: 140x140"><title>Placeholder</title><rect width="100%" height="100%" fill="#777"></rect><text x="50%" y="50%" fill="#777" dy=".3em">140x140</text></svg>
<h2>Heading</h2>
<p>Donec sed odio dui. Cras justo odio, dapibus ac facilisis in, egestas eget quam. Vestibulum id ligula porta felis euismod semper. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus.</p>
<p><a class="btn btn-secondary" href="#" role="button">View details »</a></p>
</div><!-- /.col-lg-4 -->
</div><!-- /.row -->
<!-- START THE FEATURETTES -->
<hr class="featurette-divider">
<div class="row featurette">
<div class="col-md-7">
<h2 class="featurette-heading">First featurette heading. <span class="text-muted">It’ll blow your mind.</span></h2>
<p class="lead">Donec ullamcorper nulla non metus auctor fringilla. Vestibulum id ligula porta felis euismod semper. Praesent commodo cursus magna, vel scelerisque nisl consectetur. Fusce dapibus, tellus ac cursus commodo.</p>
</div>
<div class="col-md-5">
<svg class="bd-placeholder-img bd-placeholder-img-lg featurette-image img-fluid mx-auto" width="500" height="500" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img" aria-label="Placeholder: 500x500"><title>Placeholder</title><rect width="100%" height="100%" fill="#eee"></rect><text x="50%" y="50%" fill="#aaa" dy=".3em">500x500</text></svg>
</div>
</div>
<hr class="featurette-divider">
<div class="row featurette">
<div class="col-md-7 order-md-2">
<h2 class="featurette-heading">Oh yeah, it’s that good. <span class="text-muted">See for yourself.</span></h2>
<p class="lead">Donec ullamcorper nulla non metus auctor fringilla. Vestibulum id ligula porta felis euismod semper. Praesent commodo cursus magna, vel scelerisque nisl consectetur. Fusce dapibus, tellus ac cursus commodo.</p>
</div>
<div class="col-md-5 order-md-1">
<svg class="bd-placeholder-img bd-placeholder-img-lg featurette-image img-fluid mx-auto" width="500" height="500" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img" aria-label="Placeholder: 500x500"><title>Placeholder</title><rect width="100%" height="100%" fill="#eee"></rect><text x="50%" y="50%" fill="#aaa" dy=".3em">500x500</text></svg>
</div>
</div>
<hr class="featurette-divider">
<div class="row featurette">
<div class="col-md-7">
<h2 class="featurette-heading">And lastly, this one. <span class="text-muted">Checkmate.</span></h2>
<p class="lead">Donec ullamcorper nulla non metus auctor fringilla. Vestibulum id ligula porta felis euismod semper. Praesent commodo cursus magna, vel scelerisque nisl consectetur. Fusce dapibus, tellus ac cursus commodo.</p>
</div>
<div class="col-md-5">
<svg class="bd-placeholder-img bd-placeholder-img-lg featurette-image img-fluid mx-auto" width="500" height="500" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMidYMid slice" focusable="false" role="img" aria-label="Placeholder: 500x500"><title>Placeholder</title><rect width="100%" height="100%" fill="#eee"></rect><text x="50%" y="50%" fill="#aaa" dy=".3em">500x500</text></svg>
</div>
</div>
<hr class="featurette-divider">
<!-- /END THE FEATURETTES -->
</div><!-- /.container -->
<!-- FOOTER -->
<footer class="container">
<p class="float-right"><a href="#">Back to top</a></p>
<p>© 2017-2020 Company, Inc. · <a href="#">Privacy</a> · <a href="#">Terms</a></p>
</footer>
</main>
<script src="https://code.jquery.com/jquery-3.5.1.slim.min.js" integrity="sha384-DfXdz2htPH0lsSSs5nCTpuj/zy4C+OGpamoFVy38MVBnE+IbbVYUew+OrCXaRkfj" crossorigin="anonymous"></script>
<script>window.jQuery || document.write('<script src="/docs/4.5/assets/js/vendor/jquery.slim.min.js"><\/script>')</script><script src="/docs/4.5/dist/js/bootstrap.bundle.min.js" integrity="sha384-1CmrxMRARb6aLqgBO7yyAxTOQE2AKb9GfXnEo760AUcUmFx3ibVJJAzGytlQcNXd" crossorigin="anonymous"></script>
</body>
</html>