Chrome内置的JavaScript控制台可以显示颜色吗?

我想要错误在红色,警告在橙色和控制台。log在绿色。这可能吗?


当前回答

有一系列内置函数用于为控制台日志上色:

//For pink background and red text
console.error("Hello World");  

//For yellow background and brown text
console.warn("Hello World");  

//For just a INFO symbol at the beginning of the text
console.info("Hello World");  

//for custom colored text
console.log('%cHello World','color:blue');
//here blue could be replaced by any color code

//for custom colored text with custom background text
console.log('%cHello World','background:red;color:#fff')

其他回答

下面是另一种方法(在Typescript中),它覆盖console.log函数并检查传递的消息,以便根据消息中的开始标记应用CSS格式。这个方法的一个好处是被调用者不需要使用一些包装console.log函数,他们可以坚持使用普通的console.log(),所以如果这个覆盖消失,该功能将恢复到默认的console.log:

// An example of disabling logging depending on environment:
const isLoggingEnabled = process.env.NODE_ENV !== 'production';

// Store the original logging function so we can trigger it later
const originalConsoleLog = console.log;

// Override logging to perform our own logic
console.log = (args: any) => {
    if (!isLoggingEnabled) {
        return;
    }

    // Define some tokens and their corresponding CSS
    const parsing = [
        {
            token: '[SUCCESS]',
            css: 'color: green; font-weight: bold;',
        },
        {
            token: '[ERROR]',
            css: 'color: red; font-weight: bold;',
        },
        {
            token: '[WARN]',
            css: 'color: orange; font-weight: bold;',
        },
        {
            token: '[DEBUG]',
            css: 'color: blue;',
        },
    ];

    // Currently only supports console.log(...) with a single string argument. 
    if (typeof args === 'string') {
        const message: string = args;
        let formattedArgs: string[] = [];
        for (let i = 0; i < parsing.length; i += 1) {
            const parser = parsing[i];
            if (args.startsWith(parser.token)) {
                formattedArgs = [`%c${message.substring(parser.token.length + 1, message.length)}`, parser.css];
                break;
            }
        }
        originalConsoleLog.apply(console, formattedArgs);
    } else {
        originalConsoleLog.apply(console, args);
    }
};

使用示例:

console.log('[ERROR] Something went wrong!');

输出:

看看这个:

控制台动画,加上CSS

(function() {
  var frame = 0;
  var frames = [
    "This",
    "is",
    "SPARTA!",
    " ",
    "SPARTA!",
    " ",
    "SPARTA!",
    " ",
    "SPARTA!",
    " ",
    "SPARTA!",
    " ",
    "SPARTA!"
  ];
  var showNext = () => {
    console.clear();
    console.log(
      `%c `,
      "background: red; color: white; font-size: 15px; padding: 3px 41%;"
    );
    console.log(
      `%c ${frames[frame]}`,
      "background: red; color: white; font-size: 25px; padding: 3px 40%;"
    );
    console.log(
      `%c `,
      "background: red; color: white; font-size: 15px; padding: 3px 41%;"
    );
    setTimeout(
      showNext,
      frames[frame] === "SPARTA!" || frames[frame] === " " ? 100 : 1500
    );
    // next frame and loop
    frame++;
    if (frame >= frames.length) {
      frame = 0;
    }
  };
  showNext();
})();

https://jsfiddle.net/a8y3jhfL/

你可以在每一帧中粘贴ASCII来观看ASCII动画

从Chrome 60开始,他们删除了在编写console.info时使用蓝色文本的功能,并对控制台API做了很多改变。

如果你在es6模式中写一个字符串字面值,在console.log()中使用反勾号' '作为标识符(称为模板字符串),那么下面的方法可以为控制台输出着色。

console.log(`%cToday date=>%c${new Date()}`,`color:#F74C2F`, `color:green`);
// output :Today date (in red color) => Date (in green color)

如果你想给你的终端控制台上色,那么你可以使用npm包粉笔

npm i chalk

选项1

// log-css.js v2
const log = console.log.bind()
const css = (text, options) => {
    let cssOptions = ''
    for (let prop in options) {
        const value = options[prop]
        prop = camelCaseToDashCase(prop)
        cssOptions += `${prop}: ${value}; `
    }
    return [`%c${text}`, cssOptions.trim()]

    function camelCaseToDashCase(value) {
        return value.replace(/[A-Z]/g, matched => `-${matched.toLowerCase()}`)
    }
}

例子:

log(...css('Example =P', {
    backgroundColor: 'blue',
    color: 'white',
    // fontFamily: 'Consolas',
    fontSize: '25px',
    fontWeight: '700',
    // lineHeight: '25px',
    padding: '7px 7px'
}))

选项2

我现在创建log-css.js https://codepen.io/luis7lobo9b/pen/QWyobwY

// log-css.js v1
const log = console.log.bind();
const css = function(item, color = '#fff', background = 'none', fontSize = '12px', fontWeight = 700, fontFamily) {
    return ['%c ' + item + ' ', 'color:' + color + ';background:' + background + ';font-size:' + fontSize + ';font-weight:' + fontWeight + (fontFamily ? ';font-family:' + fontFamily : '')];
};

例子:

log(...css('Lorem ipsum dolor sit amet, consectetur adipisicing elit.', 'rebeccapurple', '#000', '14px'));