要定義一個簡單的CSS過渡，需使用transition屬性並指定過渡的屬性、持續(xù)時間及可選的行為方式。 1. 選擇常用的可動畫屬性如color、background-color、opacity、transform和width；2. 避免嘗試非可動畫屬性如display或content；3. 使用瀏覽器開發(fā)者工具快速測試過渡效果；4. 基本過渡至少需指定過渡屬性和持續(xù)時間，也可加入時間函數(shù)和延遲；5. 當需要在JavaScript中響應過渡結束時，使用transitionend事件，並註意清理事件監(jiān)聽器。通過關註一兩個屬性和基本的時間設置，並根據需要進行擴展，可以保持過渡效果簡潔有效。

Defining a simple CSS transition is straightforward — it's about making a property change smoothly over time instead of snapping instantly from one state to another. The key is using the transition property (or its longhand equivalents) and specifying what you're transitioning, how fast, and optionally, how it behaves during the transition.

What properties can you transition?

Not all CSS properties are animatable, but most commonly used ones like color , background-color , opacity , transform , and width are. You don't have to guess — just try it out or refer to a list of animatable properties .

• Stick to known animatable properties for reliable results
• Avoid trying to animate non-animatable properties like display or content
• Use browser dev tools to test transitions quickly

If you're unsure whether a property will work, write the transition and see what happens in the browser. It's often the fastest way to find out.

How to set up a basic transition

To define a simple transition, you need at least two things: which property you want to transition and how long the transition should take. Here's a minimal example:

 .box {
  width: 100px;
  transition: width 0.3s;
}

.box:hover {
  width: 200px;
}

This tells the browser to animate the width change over 0.3 seconds whenever it changes — like when hovering over the element.

You can also use shorthand to include timing functions and delays:

 transition: width 0.3s ease-in-out 0.1s;

This adds a smoother acceleration/deceleration and a slight delay before starting.

When should you use transitionend ?

If you're doing something in JavaScript after a transition completes — like removing a class or triggering another animation — you'll want to listen for the transitionend event.

• Use it when you need to react to the end of a visual transition
• Be aware that it fires once per animated property , so you may want to debounce or check which property finished
• Always clean up event listeners if they're only needed once

For example:

 const box = document.querySelector('.box');

box.addEventListener('transitionend', () => {
  console.log('Transition finished');
});

It's not always necessary, but it becomes handy when coordinating transitions with JS behavior.

基本上就這些。 Keep it simple by focusing on one or two properties, start with basic timing, and expand as needed.

以上是您如何定義簡單的CSS過渡？的詳細內容。更多資訊請關注PHP中文網其他相關文章！