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

我这样写道:

//Make a copy of the old console.
var oldConsole = Object.assign({}, console);

//This function redefine the caller with the original one. (well, at least i expect this to work in chrome, not tested in others)
function setEnabled(bool) {
    if (bool) {
        //Rewrites the disable function with the original one.
        console[this.name] = oldConsole[this.name];
        //Make sure the setEnable will be callable from original one.
        console[this.name].setEnabled = setEnabled;
    } else {
        //Rewrites the original.
        var fn = function () {/*function disabled, to enable call console.fn.setEnabled(true)*/};
        //Defines the name, to remember.
        Object.defineProperty(fn, "name", {value: this.name});
        //replace the original with the empty one.
        console[this.name] = fn;
        //set the enable function
        console[this.name].setEnabled = setEnabled

    }
}

不幸的是，它在使用严格模式下不起作用。

使用console。fn。setEnabled = setEnabled然后是console。fn。setEnabled(false) fn可以是几乎任何控制台函数。 你的情况是:

console.log.setEnabled = setEnabled;
console.log.setEnabled(false);

我还写了这个:

var FLAGS = {};
    FLAGS.DEBUG = true;
    FLAGS.INFO = false;
    FLAGS.LOG = false;
    //Adding dir, table, or other would put the setEnabled on the respective console functions.

function makeThemSwitchable(opt) {
    var keysArr = Object.keys(opt);
    //its better use this type of for.
    for (var x = 0; x < keysArr.length; x++) {
        var key = keysArr[x];
        var lowerKey = key.toLowerCase();
        //Only if the key exists
        if (console[lowerKey]) {
            //define the function
            console[lowerKey].setEnabled = setEnabled;
            //Make it enabled/disabled by key.
            console[lowerKey].setEnabled(opt[key]);
        }
    }
}
//Put the set enabled function on the original console using the defined flags and set them.
makeThemSwitchable(FLAGS);

所以你只需要在FLAGS中加入默认值(在执行上面的代码之前)，比如FLAGS. log = false，日志功能将在默认情况下被禁用，仍然可以调用console.log.setEnabled(true)来启用它

令我惊讶的是，在所有这些答案中，没有人把它们结合起来:

没有jquery 匿名函数不污染全局命名空间 窗口的句柄情况。控制台未定义 只需修改控制台的.log函数

我会选这个:

(function () {

    var debug = false

    if (debug === false) {
        if ( typeof(window.console) === 'undefined') { window.console = {}; }
        window.console.log = function () {};
    }
})()

console.log('pre');
/* pre content */ 
// define a new console
let preconsole = Object.assign({}, window.console);
let aftconsole = Object.assign({}, window.console, {
    log: function(text){
        preconsole.log(text);
        preconsole.log('log');
    }
});
console = aftconsole;
/* content */

console.log('content');

/* end of content */
console = preconsole;
console.log('aft');

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

https://stackoverflow.com/a/46189791/871166的简化

switch (process.env.LOG_LEVEL) {
  case 'ERROR':
    console.warn = function() {};
  case 'WARN':
    console.info = function() {};
  case 'INFO':
    console.log = function() {};
  case 'LOG':
    console.debug = function() {};
    console.dir = function() {};
}