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The InputEvent.isComposing read-only property returns a Boolean value indicating if the event is fired after compositionstart and before compositionend.
这是一个只读属性，返回boolean类型。表示正处于输入事件的开始与结束之间，表示正在输入状态。
Syntax
var bool = event.isComposing;
Example
var inputEvent = new InputEvent("syntheticInput", false);
console.log(inputEvent.isComposing); // return false
Specifications
| Specification | Status | Comment |
|---|---|---|
| Document Object Model (DOM) Level 3 Events Specification InputEvent.isComposing |
Working Draft | Initial definition. |
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
|---|---|---|---|---|---|
| Basic support | 未实现 | 31.0 (31.0) | 未实现 | 未实现 | 未实现 |
| Feature | Android | Firefox Mobile (Gecko) | IE Phone | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|
| Basic support | 未实现 | 31.0 (31.0) | 未实现 | 未实现 | 未实现 |