debugger

debugger 语句调用任何可用的调试功能，例如设置断点。 如果没有调试功能可用，则此语句不起作用。

语法

debugger;

示例

下面的例子演示了一个包含 debugger 语句的函数，当函数被调用时，会尝试调用一个可用的调试器进行调试。

function potentiallyBuggyCode() {
    debugger;
    // do potentially buggy stuff to examine, step through, etc.
}

当 debugger 被调用时, 执行暂停在 debugger 语句的位置。就像在脚本源代码中的断点一样。

Paused at a debugger statement.

规范

Specification Status Comment
ECMAScript Latest Draft (ECMA-262)
Debugger statement		 Draft  
ECMAScript 2015 (6th Edition, ECMA-262)
Debugger statement		 Standard  
ECMAScript 5.1 (ECMA-262)
Debugger statement		 Standard Initial definition
ECMAScript 3rd Edition (ECMA-262)
Debugger statement		 Standard  
ECMAScript 1st Edition (ECMA-262)
Debugger statement		 Standard Only mentioned as reserved word.

浏览器兼容

Update compatibility data on GitHub
DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
debuggerChrome Full support 5Edge Full support 12Firefox Full support 1IE Full support 4Opera Full support YesSafari Full support YesWebView Android Full support 1Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support 1.0nodejs Full support Yes

Legend

Full support  
Full support

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