How to center multiple images vertically

Bootstrap does not directly provide multi-graph vertically centered components. It can be implemented by cleverly using flex layout: set flex-direction: flex-column (vertical direction), justify-content-center (vertical center), align-items-center (horizontal center). The container needs to set the height to ensure that the image is displayed in the center. If the image height is different, try align-content: center to adjust the vertical spacing. Appropriately use the aspect-ratio attribute to control the aspect ratio of the picture and optimize the layout.

Let your pictures be centered gracefully vertically: Bootstrap tips

How to center multiple images vertically in Bootstrap? This problem seems simple, but it is not handled well and it is easy to fall into various pitfalls. Many novices will use text-align: center directly, and they found that the picture is centered horizontally, but the vertical direction is still messy. This article will explore this issue in depth, help you thoroughly master the skills of vertical centering of multiple images under Bootstrap, and share some of my experiences summarizing over the years. After reading this article, you will no longer be worried about the vertical centering of the picture, and you can even learn from it and solve more layout problems.

First of all, we need to be clear: Bootstrap itself does not directly provide a component or property that "multi-graph vertical centering". We need to use existing tools and technologies cleverly to achieve this goal. It's like building a castle with building blocks, Bootstrap provides a variety of building blocks, and we need to combine them reasonably.

Let's review the relevant Bootstrap basics. display: flex is a powerful tool that gives elements powerful layout capabilities. It is crucial to understand the three attributes of flex-direction , align-items and justify-content . They control the spindle direction, cross-axis alignment and spindle alignment of elements in the flex container respectively.

Now, let's see how to use flex to achieve multi-graph vertical centering. The simplest solution is to use a flex container to wrap all the pictures:

 <code class="html"><div class="container d-flex flex-column justify-content-center align-items-center" style="height: 300px;"> <img class="img-fluid lazy" src="/static/imghwm/default1.png" data-src="image1.jpg" alt="Image 1"> <img class="img-fluid lazy" src="/static/imghwm/default1.png" data-src="image2.jpg" alt="Image 2"> <img class="img-fluid lazy" src="/static/imghwm/default1.png" data-src="image3.jpg" alt="Image 3"> </div></code>

Here, d-flex enables flex layout, flex-column sets the spindle direction to be vertical, justify-content-center centers the picture in the vertical direction, and align-items-center centers the picture in the horizontal direction. img-fluid class allows the image to automatically adapt to the container width and maintain the proportion. height: 300px; Set the container height to ensure that there is enough space for the image to be centered. Remember, setting the container height is key, otherwise the image will not be centered.

This is a simple and effective solution, but it also has limitations. If the number of pictures is large or the height of pictures is different, the effect of this solution may not be ideal. At this time, you may need to consider more complex layout solutions, such as using a grid system or more advanced flex layout techniques.

Next, let's discuss some potential problems and solutions. For example, if the image is inconsistent in height, align-items: center may not achieve the desired effect. At this point, you can try using align-content: center , but this will affect the vertical spacing of the image. You need to make adjustments according to actual conditions. In addition, aspect-ratio attribute of the image can also help you control the aspect ratio of the image, thereby better controlling the layout.

Finally, regarding performance optimization, try to avoid unnecessary nesting and redundant code. Choosing the appropriate image format and size can also improve page loading speed. Remember, clean code is not only easy to maintain, but also performs better. A good programmer always pursues the elegance and efficiency of code. This is not just technology, it is also an art. I hope this article can help you better understand the vertical centering of images in Bootstrap and improve your front-end development capabilities.

The above is the detailed content of How to center multiple images vertically. For more information, please follow other related articles on the PHP Chinese website!