58 个 JS 实用工具函数，快速提升项目开发效率

TIP

收集和封装工具是一名优秀的前端工程师必备的技能之一，对我们日常开发真的是拿来即用，不再等用到了再去写，如果业务需求有变化只需要迭代更新就好。

目前总结了项目中 12 种类型 58 个 JavaScript 实用工具函数的最佳实践，马上就能用起来。

一、浏览器操作

TIP

• 滚动到页面顶部，滚动到页面底部，滚动到指定元素区域
• 获取可视窗口高度，获取可视窗口宽度
• 打开浏览器全屏，退出浏览器全屏

1、滚动到页面顶部

export const scrollToTop = () => {
  const height = document.documentElement.scrollTop || document.body.scrollTop;
  if (height > 0) {
    window.requestAnimationFrame(scrollToTop);
    window.scrollTo(0, height - height / 8);
  }
};

2、滚动到页面底部

export const scrollToBottom = () => {
  window.scrollTo(0, document.documentElement.clientHeight);
};

3、滚动到指定元素区域

export const smoothScroll = (element) => {
  document.querySelector(element).scrollIntoView({
    behavior: "smooth",
  });
};

4、获取可视窗口高度

export const getClientHeight = () => {
  let clientHeight = 0;
  if (document.body.clientHeight && document.documentElement.clientHeight) {
    clientHeight =
      document.body.clientHeight < document.documentElement.clientHeight
        ? document.body.clientHeight
        : document.documentElement.clientHeight;
  } else {
    clientHeight =
      document.body.clientHeight > document.documentElement.clientHeight
        ? document.body.clientHeight
        : document.documentElement.clientHeight;
  }
  return clientHeight;
};

5、获取可视窗口宽度

export const getPageViewWidth = () => {
  return (
    document.compatMode == "BackCompat"
      ? document.body
      : document.documentElement
  ).clientWidth;
};

6、打开浏览器全屏

export const toFullScreen = () => {
  let element = document.body;
  if (element.requestFullscreen) {
    element.requestFullscreen();
  } else if (element.mozRequestFullScreen) {
    element.mozRequestFullScreen();
  } else if (element.msRequestFullscreen) {
    element.msRequestFullscreen();
  } else if (element.webkitRequestFullscreen) {
    element.webkitRequestFullScreen();
  }
};

7、退出浏览器全屏

export const exitFullscreen = () => {
  if (document.exitFullscreen) {
    document.exitFullscreen();
  } else if (document.msExitFullscreen) {
    document.msExitFullscreen();
  } else if (document.mozCancelFullScreen) {
    document.mozCancelFullScreen();
  } else if (document.webkitExitFullscreen) {
    document.webkitExitFullscreen();
  }
};

二、设备判断

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• 判断是移动还是 PC 设备，判断是否是苹果还是安卓移动设备
• 判断是否是安卓移动设备，判断是 Windows 还是 Mac 系统
• 判断是否是微信/QQ 内置浏览器，浏览器类型和版本

1、判断是移动还是 PC 设备

export const isMobile = () => {
  if (
    navigator.userAgent.match(
      /(iPhone|iPod|Android|ios|iOS|iPad|Backerry|WebOS|Symbian|Windows Phone|Phone)/i
    )
  ) {
    return "mobile";
  }
  return "desktop";
};

2、判断是否是苹果还是安卓移动设备

export const isAppleMobileDevice = () => {
  let reg = /iphone|ipod|ipad|Macintosh/i;
  return reg.test(navigator.userAgent.toLowerCase());
};

3、判断是否是安卓移动设备

export const isAndroidMobileDevice = () => {
  return /android/i.test(navigator.userAgent.toLowerCase());
};

4、判断是 Windows 还是 Mac 系统

export const osType = () => {
  const agent = navigator.userAgent.toLowerCase();
  const isMac = /macintosh|mac os x/i.test(navigator.userAgent);
  const isWindows =
    agent.indexOf("win64") >= 0 ||
    agent.indexOf("wow64") >= 0 ||
    agent.indexOf("win32") >= 0 ||
    agent.indexOf("wow32") >= 0;
  if (isWindows) {
    return "windows";
  }
  if (isMac) {
    return "mac";
  }
};

5、判断是否是微信/QQ 内置浏览器

export const broswer = () => {
  const ua = navigator.userAgent.toLowerCase();
  if (ua.match(/MicroMessenger/i) == "micromessenger") {
    return "weixin";
  } else if (ua.match(/QQ/i) == "qq") {
    return "QQ";
  }
  return false;
};

6、浏览器型号和版本

export const getExplorerInfo = () => {
  let t = navigator.userAgent.toLowerCase();
  return 0 <= t.indexOf("msie")
    ? {
        //ie < 11
        type: "IE",
        version: Number(t.match(/msie ([\d]+)/)[1]),
      }
    : !!t.match(/trident\/.+?rv:(([\d.]+))/)
    ? {
        // ie 11
        type: "IE",
        version: 11,
      }
    : 0 <= t.indexOf("edge")
    ? {
        type: "Edge",
        version: Number(t.match(/edge\/([\d]+)/)[1]),
      }
    : 0 <= t.indexOf("firefox")
    ? {
        type: "Firefox",
        version: Number(t.match(/firefox\/([\d]+)/)[1]),
      }
    : 0 <= t.indexOf("chrome")
    ? {
        type: "Chrome",
        version: Number(t.match(/chrome\/([\d]+)/)[1]),
      }
    : 0 <= t.indexOf("opera")
    ? {
        type: "Opera",
        version: Number(t.match(/opera.([\d]+)/)[1]),
      }
    : 0 <= t.indexOf("Safari")
    ? {
        type: "Safari",
        version: Number(t.match(/version\/([\d]+)/)[1]),
      }
    : {
        type: t,
        version: -1,
      };
};

三、操作 URL

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• 获取 URL 参数列表，检测 URL 是否有效
• 键值对拼接成 URL 参数，修改 URL 中的参数，删除 URL 中指定参数

1、获取 URL 参数列表

export const GetRequest = () => {
  let url = location.search;
  const paramsStr = /.+\?(.+)$/.exec(url)[1]; // 将 ? 后面的字符串取出来
  const paramsArr = paramsStr.split("&"); // 将字符串以 & 分割后存到数组中
  let paramsObj = {};
  // 将 params 存到对象中
  paramsArr.forEach((param) => {
    if (/=/.test(param)) {
      // 处理有 value 的参数
      let [key, val] = param.split("="); // 分割 key 和 value
      val = decodeURIComponent(val); // 解码
      val = /^\d+$/.test(val) ? parseFloat(val) : val; // 判断是否转为数字
      if (paramsObj.hasOwnProperty(key)) {
        // 如果对象有 key，则添加一个值
        paramsObj[key] = [].concat(paramsObj[key], val);
      } else {
        // 如果对象没有这个 key，创建 key 并设置值
        paramsObj[key] = val;
      }
    } else {
      // 处理没有 value 的参数
      paramsObj[param] = true;
    }
  });
  return paramsObj;
};

2、检测 URL 是否有效

export const getUrlState = (URL) => {
  let xmlhttp = new ActiveXObject("microsoft.xmlhttp");
  xmlhttp.Open("GET", URL, false);
  try {
    xmlhttp.Send();
  } catch (e) {
  } finally {
    let result = xmlhttp.responseText;
    if (result) {
      if (xmlhttp.Status == 200) {
        return true;
      } else {
        return false;
      }
    } else {
      return false;
    }
  }
};

3、键值对拼接成 URL 参数

export const params2Url = (obj) => {
  let params = [];
  for (let key in obj) {
    params.push(`${key}=${obj[key]}`);
  }
  return encodeURIComponent(params.join("&"));
};

4、修改 URL 中的参数

export const replaceParamVal => (paramName, replaceWith) {
   const oUrl = location.href.toString();
   const re = eval('/('+ paramName+'=)([^&]*)/gi');
   location.href = oUrl.replace(re,paramName+'='+replaceWith);
   return location.href;
}

5、删除 URL 中指定参数

export const funcUrlDel = (name) => {
  const baseUrl = location.origin + location.pathname + "?";
  const query = location.search.substr(1);
  if (query.indexOf(name) > -1) {
    const obj = {};
    const arr = query.split("&");
    for (let i = 0; i < arr.length; i++) {
      arr[i] = arr[i].split("=");
      obj[arr[i][0]] = arr[i][1];
    }
    delete obj[name];
    return (
      baseUrl +
      JSON.stringify(obj)
        .replace(/[\"\{\}]/g, "")
        .replace(/\:/g, "=")
        .replace(/\,/g, "&")
    );
  }
};

四、格式校验

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• 校验身份证号码，校验是否包含中文
• 校验是否为中国大陆的邮政编码，校验是否为 IPv6 地址
• 校验是否为邮箱地址，校验是否为中国大陆手机号，校验是否包含 emoj 表情

1、校验身份证号码

export const checkCardNo = (value) => {
  let reg = /(^\d{15}$)|(^\d{18}$)|(^\d{17}(\d|X|x)$)/;
  return reg.test(value);
};

2、校验是否包含中文

export const haveCNChars => (value) => {
    return /[\u4e00-\u9fa5]/.test(value);
}

3、校验是否为中国大陆的邮政编码

export const isPostCode = (value) => {
  return /^[1-9][0-9]{5}$/.test(value.toString());
};

4、校验是否为 IPv6 地址

export const isIPv6 = (str) => {
  return Boolean(
    str.match(/:/g)
      ? str.match(/:/g).length <= 7
      : false && /::/.test(str)
      ? /^([\da-f]{1,4}(:|::)){1,6}[\da-f]{1,4}$/i.test(str)
      : /^([\da-f]{1,4}:){7}[\da-f]{1,4}$/i.test(str)
  );
};

5、校验是否为邮箱地址

export const isEmail = (value) {
    return /^[a-zA-Z0-9_-]+@[a-zA-Z0-9_-]+(\.[a-zA-Z0-9_-]+)+$/.test(value);
}

6、校验是否为中国大陆手机号

export const isTel = (value) => {
  return /^1[3,4,5,6,7,8,9][0-9]{9}$/.test(value.toString());
};

7、校验是否包含 emoji 表情

export const isEmojiCharacter = (value) => {
  value = String(value);
  for (let i = 0; i < value.length; i++) {
    const hs = value.charCodeAt(i);
    if (0xd800 <= hs && hs <= 0xdbff) {
      if (value.length > 1) {
        const ls = value.charCodeAt(i + 1);
        const uc = (hs - 0xd800) * 0x400 + (ls - 0xdc00) + 0x10000;
        if (0x1d000 <= uc && uc <= 0x1f77f) {
          return true;
        }
      }
    } else if (value.length > 1) {
      const ls = value.charCodeAt(i + 1);
      if (ls == 0x20e3) {
        return true;
      }
    } else {
      if (0x2100 <= hs && hs <= 0x27ff) {
        return true;
      } else if (0x2b05 <= hs && hs <= 0x2b07) {
        return true;
      } else if (0x2934 <= hs && hs <= 0x2935) {
        return true;
      } else if (0x3297 <= hs && hs <= 0x3299) {
        return true;
      } else if (
        hs == 0xa9 ||
        hs == 0xae ||
        hs == 0x303d ||
        hs == 0x3030 ||
        hs == 0x2b55 ||
        hs == 0x2b1c ||
        hs == 0x2b1b ||
        hs == 0x2b50
      ) {
        return true;
      }
    }
  }
  return false;
};

五、数字操作

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• 生成指定范围随机数，数字千分位分隔

1、生成指定范围随机数

export const randomNum = (min, max) =>
  Math.floor(Math.random() * (max - min + 1)) + min;

2、数字千分位分隔

export const format = (n) => {
  let num = n.toString();
  let len = num.length;
  if (len <= 3) {
    return num;
  } else {
    let temp = "";
    let remainder = len % 3;
    if (remainder > 0) {
      // 不是3的整数倍
      return (
        num.slice(0, remainder) +
        "," +
        num.slice(remainder, len).match(/\d{3}/g).join(",") +
        temp
      );
    } else {
      // 3的整数倍
      return num.slice(0, len).match(/\d{3}/g).join(",") + temp;
    }
  }
};

六、操作 Cookie

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• 设置 cookie，读取 cookie，删除 cookie

1、设置 cookie

export const setCookie = (key, value, expire) => {
  const d = new Date();
  d.setDate(d.getDate() + expire);
  document.cookie = `${key}=${value};expires=${d.toUTCString()}`;
};

2、读取 cookie

export const getCookie = (key) => {
  const cookieStr = unescape(document.cookie);
  const arr = cookieStr.split("; ");
  let cookieValue = "";
  for (let i = 0; i < arr.length; i++) {
    const temp = arr[i].split("=");
    if (temp[0] === key) {
      cookieValue = temp[1];
      break;
    }
  }
  return cookieValue;
};

3、删除 cookie

export const delCookie = (key) => {
  document.cookie = `${encodeURIComponent(key)}=;expires=${new Date()}`;
};

七、操作存储

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• 存储 loalStorage，获取 localStorage，删除 localStorage
• 存储 sessionStorage，获取 sessionStorage，删除 sessionStorage

1、存储 loalStorage

export const loalStorageSet = (key, value) => {
  if (!key) return;
  if (typeof value !== "string") {
    value = JSON.stringify(value);
  }
  window.localStorage.setItem(key, value);
};

2、获取 localStorage

export const loalStorageGet = (key) => {
  if (!key) return;
  return window.localStorage.getItem(key);
};

3、删除 localStorage

export const loalStorageRemove = (key) => {
  if (!key) return;
  window.localStorage.removeItem(key);
};

4、存储 sessionStorage

export const sessionStorageSet = (key, value) => {
  if (!key) return;
  if (typeof value !== "string") {
    value = JSON.stringify(value);
  }
  window.sessionStorage.setItem(key, value);
};

5、获取 sessionStorage

export const sessionStorageGet = (key) => {
  if (!key) return;
  return window.sessionStorage.getItem(key);
};

6、删除 sessionStorage

export const sessionStorageRemove = (key) => {
  if (!key) return;
  window.sessionStorage.removeItem(key);
};

八、格式转化

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• 数字转化为大写金额
• 数字转化为中文数字

1、数字转化为大写金额

export const digitUppercase = (n) => {
  const fraction = ["角", "分"];
  const digit = ["零", "壹", "贰", "叁", "肆", "伍", "陆", "柒", "捌", "玖"];
  const unit = [
    ["元", "万", "亿"],
    ["", "拾", "佰", "仟"],
  ];
  n = Math.abs(n);
  let s = "";
  for (let i = 0; i < fraction.length; i++) {
    s += (
      digit[Math.floor(n * 10 * Math.pow(10, i)) % 10] + fraction[i]
    ).replace(/零./, "");
  }
  s = s || "整";
  n = Math.floor(n);
  for (let i = 0; i < unit[0].length && n > 0; i++) {
    let p = "";
    for (let j = 0; j < unit[1].length && n > 0; j++) {
      p = digit[n % 10] + unit[1][j] + p;
      n = Math.floor(n / 10);
    }
    s = p.replace(/(零.)*零$/, "").replace(/^$/, "零") + unit[0][i] + s;
  }
  return s
    .replace(/(零.)*零元/, "元")
    .replace(/(零.)+/g, "零")
    .replace(/^整$/, "零元整");
};

2、数字转化为中文数字

export const intToChinese = (value) => {
  const str = String(value);
  const len = str.length - 1;
  const idxs = [
    "",
    "十",
    "百",
    "千",
    "万",
    "十",
    "百",
    "千",
    "亿",
    "十",
    "百",
    "千",
    "万",
    "十",
    "百",
    "千",
    "亿",
  ];
  const num = ["零", "一", "二", "三", "四", "五", "六", "七", "八", "九"];
  return str.replace(/([1-9]|0+)/g, ($, $1, idx, full) => {
    let pos = 0;
    if ($1[0] !== "0") {
      pos = len - idx;
      if (idx == 0 && $1[0] == 1 && idxs[len - idx] == "十") {
        return idxs[len - idx];
      }
      return num[$1[0]] + idxs[len - idx];
    } else {
      let left = len - idx;
      let right = len - idx + $1.length;
      if (Math.floor(right / 4) - Math.floor(left / 4) > 0) {
        pos = left - (left % 4);
      }
      if (pos) {
        return idxs[pos] + num[$1[0]];
      } else if (idx + $1.length >= len) {
        return "";
      } else {
        return num[$1[0]];
      }
    }
  });
};

九、字符串操作

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• 生成随机字符串，字符串首字母大写。手机号中间四位变成*
• 骆驼命名转换成短横线命名，短横线命名转换成骆驼命名
• 全角转换为半角，半角转换为全角

1、生成随机字符串

export const randomString = (len) => {
  let chars = "ABCDEFGHJKMNPQRSTWXYZabcdefhijkmnprstwxyz123456789";
  let strLen = chars.length;
  let randomStr = "";
  for (let i = 0; i < len; i++) {
    randomStr += chars.charAt(Math.floor(Math.random() * strLen));
  }
  return randomStr;
};

2、字符串首字母大写

export const fistLetterUpper = (str) => {
  return str.charAt(0).toUpperCase() + str.slice(1);
};

3、手机号中间四位变成*

export const telFormat = (tel) => {
  tel = String(tel);
  return tel.substr(0, 3) + "****" + tel.substr(7);
};

4、驼峰命名转换成短横线命名

export const getKebabCase = (str) => {
  return str.replace(/[A-Z]/g, (item) => "-" + item.toLowerCase());
};

5、短横线命名转换成驼峰命名

export const getCamelCase = (str) => {
  return str.replace(/-([a-z])/g, (i, item) => item.toUpperCase());
};

6、全角转换为半角

export const toCDB = (str) => {
  let result = "";
  for (let i = 0; i < str.length; i++) {
    code = str.charCodeAt(i);
    if (code >= 65281 && code <= 65374) {
      result += String.fromCharCode(str.charCodeAt(i) - 65248);
    } else if (code == 12288) {
      result += String.fromCharCode(str.charCodeAt(i) - 12288 + 32);
    } else {
      result += str.charAt(i);
    }
  }
  return result;
};

7、半角转换为全角

export const toDBC = (str) => {
  let result = "";
  for (let i = 0; i < str.length; i++) {
    code = str.charCodeAt(i);
    if (code >= 33 && code <= 126) {
      result += String.fromCharCode(str.charCodeAt(i) + 65248);
    } else if (code == 32) {
      result += String.fromCharCode(str.charCodeAt(i) + 12288 - 32);
    } else {
      result += str.charAt(i);
    }
  }
  return result;
};

十、时间操作

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• 当前时间
• 格式化时间

1、当前时间

export const nowTime = () => {
  const now = new Date();
  const year = now.getFullYear();
  const month = now.getMonth();
  const date = now.getDate() >= 10 ? now.getDate() : "0" + now.getDate();
  const hour = now.getHours() >= 10 ? now.getHours() : "0" + now.getHours();
  const miu =
    now.getMinutes() >= 10 ? now.getMinutes() : "0" + now.getMinutes();
  const sec =
    now.getSeconds() >= 10 ? now.getSeconds() : "0" + now.getSeconds();
  return (
    +year +
    "年" +
    (month + 1) +
    "月" +
    date +
    "日 " +
    hour +
    ":" +
    miu +
    ":" +
    sec
  );
};

2、格式化时间

export const dateFormater = (formater, time) => {
  let date = time ? new Date(time) : new Date(),
    Y = date.getFullYear() + "",
    M = date.getMonth() + 1,
    D = date.getDate(),
    H = date.getHours(),
    m = date.getMinutes(),
    s = date.getSeconds();
  return formater
    .replace(/YYYY|yyyy/g, Y)
    .replace(/YY|yy/g, Y.substr(2, 2))
    .replace(/MM/g, (M < 10 ? "0" : "") + M)
    .replace(/DD/g, (D < 10 ? "0" : "") + D)
    .replace(/HH|hh/g, (H < 10 ? "0" : "") + H)
    .replace(/mm/g, (m < 10 ? "0" : "") + m)
    .replace(/ss/g, (s < 10 ? "0" : "") + s);
};
// dateFormater('YYYY-MM-DD HH:mm:ss')
// dateFormater('YYYYMMDDHHmmss')

十一、JavaScript 操作

TIP

• 阻止冒泡事件
• 防抖函数，节流函数
• 数据类型判断，对象深拷贝

1、阻止冒泡事件

export const stopPropagation = (e) => {
  e = e || window.event;
  if (e.stopPropagation) {
    // W3C阻止冒泡方法
    e.stopPropagation();
  } else {
    e.cancelBubble = true; // IE阻止冒泡方法
  }
};

2、防抖函数

export const debounce = (fn, wait) => {
  let timer = null;

  return function () {
    let context = this,
      args = arguments;

    if (timer) {
      clearTimeout(timer);
      timer = null;
    }

    timer = setTimeout(() => {
      fn.apply(context, args);
    }, wait);
  };
};

3、节流函数

export const throttle = (fn, delay) => {
  let curTime = Date.now();

  return function () {
    let context = this,
      args = arguments,
      nowTime = Date.now();

    if (nowTime - curTime >= delay) {
      curTime = Date.now();
      return fn.apply(context, args);
    }
  };
};

4、数据类型判断

export const getType = (value) => {
  if (value === null) {
    return value + "";
  }
  // 判断数据是引用类型的情况
  if (typeof value === "object") {
    let valueClass = Object.prototype.toString.call(value),
      type = valueClass.split(" ")[1].split("");
    type.pop();
    return type.join("").toLowerCase();
  } else {
    // 判断数据是基本数据类型的情况和函数的情况
    return typeof value;
  }
};

5、对象深拷贝

export const deepClone = (obj, hash = new WeakMap()) => {
  // 日期对象直接返回一个新的日期对象
  if (obj instanceof Date) {
    return new Date(obj);
  }
  //正则对象直接返回一个新的正则对象
  if (obj instanceof RegExp) {
    return new RegExp(obj);
  }
  //如果循环引用,就用 weakMap 来解决
  if (hash.has(obj)) {
    return hash.get(obj);
  }
  // 获取对象所有自身属性的描述
  let allDesc = Object.getOwnPropertyDescriptors(obj);
  // 遍历传入参数所有键的特性
  let cloneObj = Object.create(Object.getPrototypeOf(obj), allDesc);

  hash.set(obj, cloneObj);
  for (let key of Reflect.ownKeys(obj)) {
    if (typeof obj[key] === "object" && obj[key] !== null) {
      cloneObj[key] = deepClone(obj[key], hash);
    } else {
      cloneObj[key] = obj[key];
    }
  }
  return cloneObj;
};

十二、数组操作

TIP

• 数组操作，数组乱序
• 数组扁平化，数组去重，数组中获取随机数

1、数组乱序

export const arrScrambling = (arr) => {
  for (let i = 0; i < arr.length; i++) {
    const randomIndex = Math.round(Math.random() * (arr.length - 1 - i)) + i;
    [arr[i], arr[randomIndex]] = [arr[randomIndex], arr[i]];
  }
  return arr;
};

2、数组扁平化

export const flatten = (arr) => {
  let result = [];

  for (let i = 0; i < arr.length; i++) {
    if (Array.isArray(arr[i])) {
      result = result.concat(flatten(arr[i]));
    } else {
      result.push(arr[i]);
    }
  }
  return result;
};

3、数组中获取随机数

export const sample = (arr) => arr[Math.floor(Math.random() * arr.length)];