Bootstrap 4 responsive image with set height - html

Question

If I have a card inside a column, that needs to have an image with a set height, how do I make it not stretched out, as it currently is in my code example? And without having to have a set width on the image because I want it to be replaceable.
What am I missing and/or doing wrong? Thanks!
.card-block {
padding: 20px;
}
<link href="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/4.0.0-beta.2/css/bootstrap.css" rel="stylesheet" />
<div class="col-md-6">
<div class="card">
<img class="card-img-top" src="https://placeimg.com/640/480/animals" alt="Card image cap" height="200">
<div class="card-block text-center">
<p class="card-text">Text goes here</p>
<p class="card-subtitle">More text goes here</p>
</div>
</div>
</div>

Answer 1

Your best solution is to instead of placing the image directly onto the page you can create an empty div and then set the background image to be https://placeimg.com/640/480/animals then set its size to cover and then it will cover the height and width of the div you have specified
so for example...
css
card-image-container{
background: url('https://placeimg.com/640/480/animals') 50% no-repeat;
background-size: cover;
}

Answer 2

Making an image responsive in Bootstrap 4 is very easy:
You just add the img-fluid class to the image.
HOWEVER... responsiveness comes at a cost and that is: You cannot set a minimum height for a responsive image (because that in itself would make the image non-responsive).
Luckily, there are a few workarounds for managing the size of your card image while still keeping it responsive. You can do that by manipulating the horizontal padding (use the px-* class and swap the * for a number between 0 and 5) as well as increasing or decreasing the column width.
Take a look at the 3 examples here:
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
<div class="container">
<div class="row mt-3">
<div class="col-md-6">
<div class="card">
<img class="card-img-top img-fluid" src="https://placeimg.com/640/480/animals" alt="Card image cap">
<div class="card-block text-center">
<p class="card-text">Text goes here</p>
<p class="card-subtitle">More text goes here</p>
</div>
</div>
</div>
</div>
<div class="row mt-3">
<div class="col-md-6 px-5">
<div class="card">
<img class="card-img-top img-fluid" src="https://placeimg.com/640/480/animals" alt="Card image cap">
<div class="card-block text-center">
<p class="card-text">Column with px-5 class</p>
<p class="card-subtitle">to make the image smaller</p>
</div>
</div>
</div>
</div>
<div class="row mt-3">
<div class="col-5 px-5">
<div class="card">
<img class="card-img-top img-fluid" src="https://placeimg.com/640/480/animals" alt="Card image cap">
<div class="card-block text-center">
<p class="card-text">Smaller column AND px-5 class</p>
<p class="card-subtitle">to make the image even smaller!</p>
</div>
</div>
</div>
</div>
</div>

Answer 3

Usually, when using Bootstrap you should use div with the class of container or container-fluid and after that div with the class of row. This worked for me
<div class="container">
<div class="row">
<div class="col-md-6">
<div class="card">
<img class="card-img-top" src="https://placeimg.com/640/480/animals"
alt="Card image cap" height="200">
<div class="card-body text-center">
<p class="card-text">Text goes here</p>
<p class="card-subtitle">More text goes here</p>
</div>
</div>
</div>
</div>
</div>
Cards know to be pain in the.. But I hope this helps.