What does overflow mean in web pages?

Overflow in web pages is a CSS property used to control the handling of content when the content in the container element overflows. It can define behaviors such as scrolling, hiding or automatic expansion when the content inside the container element exceeds the boundaries of the container. You can Applies to any container element with fixed height and width. By setting values ​​such as visible, hidden, scroll, or auto, you can achieve effects such as displaying, hiding, and scrolling of content. Proper use of the overflow attribute can improve the usability and user experience of web pages.

The operating system for this tutorial: Windows 10 system, DELL G3 computer.

In web design, overflow is a CSS property used to control how content in a container element overflows. It can define behaviors such as scrolling, hiding, or automatic expansion when the content inside the container element exceeds the boundaries of the container. The overflow attribute has the following commonly used values:

1. visible: default value. When content exceeds the bounds of the container, it appears outside the container and may cover other elements. In this case, no scroll bars will appear on the container.

2. hidden: When the content exceeds the boundary of the container, it will be cropped and hidden and will not be displayed outside the container. In this case, no scroll bars will appear on the container.

3. scroll: When the content exceeds the boundary of the container, a scroll bar will be displayed so that the user can scroll to view the exceeded content. A hidden scrollbar is displayed even if the content does not exceed the container bounds.

4. auto: When the content exceeds the boundary of the container, scroll bars will be displayed as needed. If the content does not exceed the bounds of the container, no scroll bars will be displayed.

The overflow attribute can be applied to any container element with fixed height and width, such as div, span, iframe, etc. By setting the overflow attribute, you can better control how the content in the container is displayed to adapt to different design needs.

Using the overflow attribute can achieve the following effects:

1. Scroll: When the content exceeds the boundary of the container, by setting overflow: scroll, the scroll bar can be displayed inside the container so that the user can scroll to view Exceeded content. This is useful when you need to display a lot of content but don't want the page to be too long.

2. Hidden: By setting overflow: hidden, you can hide content beyond the boundaries of the container so that it is not displayed outside the container. This is useful in situations where you need to control container dimensions and hide overflowing content.

3. Automatic expansion: By setting overflow: auto, you can decide whether to display scroll bars based on the actual size of the content. If the content exceeds the boundaries of the container, scroll bars will be displayed to allow the user to scroll; if the content does not exceed the boundaries of the container, scroll bars will not be displayed.

It should be noted that the overflow attribute only works on container elements with fixed height and width. For container elements that do not have a set height or width, the overflow attribute will not take effect.

To summarize, the overflow attribute is used to control how the content in the container element overflows. By setting values ​​such as visible, hidden, scroll, or auto, you can achieve effects such as displaying, hiding, and scrolling of content. Reasonable use of the overflow attribute can improve the usability and user experience of web pages.

The above is the detailed content of What does overflow mean in web pages?. For more information, please follow other related articles on the PHP Chinese website!