是否有任何方法关闭我的JavaScript代码中的所有console.log语句,用于测试目的?
当前回答
这是来自SolutionYogi和Chris s的答案的混合。它维护console.log行号和文件名。jsFiddle示例。
// Avoid global functions via a self calling anonymous one (uses jQuery)
(function(MYAPP, $, undefined) {
// Prevent errors in browsers without console.log
if (!window.console) window.console = {};
if (!window.console.log) window.console.log = function(){};
//Private var
var console_log = console.log;
//Public methods
MYAPP.enableLog = function enableLogger() { console.log = console_log; };
MYAPP.disableLog = function disableLogger() { console.log = function() {}; };
}(window.MYAPP = window.MYAPP || {}, jQuery));
// Example Usage:
$(function() {
MYAPP.disableLog();
console.log('this should not show');
MYAPP.enableLog();
console.log('This will show');
});
其他回答
据我从文档中得知,Firebug没有提供任何变量来切换调试状态。相反,将console.log()包装在一个有条件地调用它的包装器中,即:
DEBUG = true; // set to false to disable debugging
function debug_log() {
if ( DEBUG ) {
console.log.apply(this, arguments);
}
}
为了不需要改变所有现有的调用,你可以使用这个代替:
DEBUG = true; // set to false to disable debugging
old_console_log = console.log;
console.log = function() {
if ( DEBUG ) {
old_console_log.apply(this, arguments);
}
}
我之前用过温斯顿记录器。
现在,我使用以下简单的代码从经验:
从cmd/命令行设置环境变量(在Windows上): cmd setx LOG_LEVEL信息
或者,如果你愿意,你可以在你的代码中有一个变量,但上面更好。
Restart cmd/ command line, or, IDE/ editor like Netbeans Have below like code: console.debug = console.log; // define debug function console.silly = console.log; // define silly function switch (process.env.LOG_LEVEL) { case 'debug': case 'silly': // print everything break; case 'dir': case 'log': console.debug = function () {}; console.silly = function () {}; break; case 'info': console.debug = function () {}; console.silly = function () {}; console.dir = function () {}; console.log = function () {}; break; case 'trace': // similar to error, both may print stack trace/ frames case 'warn': // since warn() function is an alias for error() case 'error': console.debug = function () {}; console.silly = function () {}; console.dir = function () {}; console.log = function () {}; console.info = function () {}; break; } Now use all console.* as below: console.error(' this is a error message '); // will print console.warn(' this is a warn message '); // will print console.trace(' this is a trace message '); // will print console.info(' this is a info message '); // will print, LOG_LEVEL is set to this console.log(' this is a log message '); // will NOT print console.dir(' this is a dir message '); // will NOT print console.silly(' this is a silly message '); // will NOT print console.debug(' this is a debug message '); // will NOT print
现在,根据点1中的LOG_LEVEL设置(例如,setx LOG_LEVEL日志和重新启动命令行),上面的一些将打印,其他将不打印
希望这有帮助。
我认为2020年最简单、最容易理解的方法是创建一个像log()这样的全局函数,你可以选择以下方法之一:
const debugging = true;
function log(toLog) {
if (debugging) {
console.log(toLog);
}
}
function log(toLog) {
if (true) { // You could manually change it (Annoying, though)
console.log(toLog);
}
}
你可以说这些功能的缺点是:
您仍然在运行时调用函数 您必须记住在第二个选项中更改调试变量或if语句 您需要确保在加载所有其他文件之前加载了该函数
And my retorts to these statements is that this is the only method that won't completely remove the console or console.log function which I think is bad programming because other developers who are working on the website would have to realize that you ignorantly removed them. Also, you can't edit JavaScript source code in JavaScript, so if you really want something to just wipe all of those from the code you could use a minifier that minifies your code and removes all console.logs. Now, the choice is yours, what will you do?
当使用React时,你可以利用钩子来管理它,这样它就被限制在你的组件范围内
import { useEffect, useRef } from "react";
type LoggingReplacements = {
debug?: typeof console["debug"];
error?: typeof console["error"];
info?: typeof console["info"];
log?: typeof console["log"];
warn?: typeof console["warn"];
};
/**
* This replaces console.XXX loggers with custom implementations. It will restore console log on unmount of the component.
* @param replacements a map of replacement loggers. They're all optional and only the functions defined will be replaced.
*/
export function useReplaceLogging({
debug,
error,
info,
log,
warn,
}: LoggingReplacements): void {
const originalConsoleDebug = useRef(console.debug);
const originalConsoleError = useRef(console.error);
const originalConsoleInfo = useRef(console.info);
const originalConsoleLog = useRef(console.log);
const originalConsoleWarn = useRef(console.warn);
if (debug) {
console.debug = debug;
}
if (error) {
console.error = error;
}
if (info) {
console.info = info;
}
if (log) {
console.log = log;
}
if (warn) {
console.warn = warn;
}
useEffect(() => {
return function restoreConsoleLog() {
console.debug = originalConsoleDebug.current;
console.error = originalConsoleError.current;
console.info = originalConsoleInfo.current;
console.log = originalConsoleLog.current;
console.warn = originalConsoleWarn.current;
};
}, []);
}
在https://github.com/trajano/react-hooks/tree/master/src/useReplaceLogging上编写测试代码
嘿~让我们用现代的2022方式来做~
ES6中引入了代理和反射。这些是我们正在寻找的工具,使console.log被条件“禁用”。
在传统的方法中,你必须创建另一个函数,像这样:
let console_disabled = true;
function console_log() {
if (!console_disabled) {
console.log.apply(console, arguments); //Dev Tools will mark the coding line here
}
}
但是,这将创建另一个函数,并且您无法使用Dev Tools中显示的编码行记录消息。
这就是2022年之路。
// Disable Console Log without altering debug coding line. // No override original `console` object let console_disabled = false; const nullFunc = function(){}; const _console = new Proxy(console, { get(target, prop, receiver){ if(prop==='log' && console_disabled){ return nullFunc; } return Reflect.get(...arguments) } }); console_disabled = true; _console.log('you cannot see me'); console_disabled = false; _console.log('you can see me @ line 18'); console_disabled = true; _console.log('you cannot see me'); console_disabled = false; _console.log('you can see me @ line 22');
您还可以重写原来的控制台对象。
// Disable Console Log without altering debug coding line. // Override original `console` object let console_disabled = false; const nullFunc = function(){}; console = new Proxy(console, { get(target, prop, receiver){ if(prop==='log' && console_disabled){ return nullFunc; } return Reflect.get(...arguments) } }); console_disabled = true; console.log('you cannot see me'); console_disabled = false; console.log('you can see me @ line 18'); console_disabled = true; console.log('you cannot see me'); console_disabled = false; console.log('you can see me @ line 22');
有关代理和反射的详细信息, 请访问https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Proxy