Document.queryCommandEnabled()

注意

该方法在部分浏览器返回的结果是不可预料的。因此,建议使用execCommand的返回值直接判断,或通过其它方式嗅探,而非使用该方法。

Document.queryCommandEnabled() 方法可查询浏览器中指定的编辑指令是否可用。

语法

var isEnabled = document.queryCommandEnabled(command);

参数

command
待查询的是否可用的指令.

返回值

返回 Boolean 值,true 表示指令可用,false表示指令不可用

备注

  • 经过测试,在部分浏览器它永远返回 false,而IE浏览器即使对于同样支持的属性也可能有不同返回值;有时IE还会对不支持的属性抛出异常而不是返回 false
  • 对于 "cut" 和 "copy" 指令,只有当用户启动的线程调用该方法时才返回true。
  • "paste" 指令不仅当特性不可用时返回 false ,脚本权限不足时也一样。

示例

var flg = document.queryCommandEnabled("SelectAll");

if(flg) {
  document.execCommand("SelectAll", false, null); // command is enabled, run it
}

规范

说明 状态 描述
HTML Editing APIs
querycommandenabled
Editor's Draft Initial definition

浏览器兼容性

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
queryCommandEnabled
DeprecatedNon-standard
Chrome Full support 1Edge Full support 12Firefox Full support 41
Full support 41
No support 9 — 41
Notes
Notes queryCommandEnabled with arguments cut, copy or paste would throw errors unless the script had special privileges.
IE Full support 4Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesFirefox Android Full support 41
Full support 41
No support 9 — 41
Notes
Notes queryCommandEnabled with arguments cut, copy or paste would throw errors unless the script had special privileges.
Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yes

Legend

Full support  
Full support
Non-standard. Expect poor cross-browser support.
Non-standard. Expect poor cross-browser support.
Deprecated. Not for use in new websites.
Deprecated. Not for use in new websites.
See implementation notes.
See implementation notes.

参考资料