1. Digital operation

(1) Generates a random number in the specified range

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

(2) Digit thousands separator

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) { // Not an integer multiple of 3
            return num.slice(0, remainder) + ',' + num.slice(remainder, len).match(/\d{3}/g).join(',') + temp;
        } else { // Integral multiple of 3
            return num.slice(0, len).match(/\d{3}/g).join(',') + temp; 
        }
    }
}

2. Array operation

(1) Array out of order

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) Array flattening

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) Get random number from array

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

3. String operation

(1) Generate random string

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) String initial uppercase

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

(3) The middle four digits of the mobile phone number become*

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

(4) Conversion of hump naming to short horizontal line naming

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

(5) Conversion of dash naming to hump naming

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

(6) Convert full angle to half angle

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) Half angle to full angle  

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;
}

4. Format conversion

(1) Convert figures to amounts in words

export const digitUppercase = (n) => {
    const fraction = ['horn', 'branch'];
    const digit = [
        'Fatal Frame', 'one', 'two', 'three', 'four',
        'five', 'land', 'seven', 'eight', 'nine'
    ];
    const unit = [
        ['element', 'ten thousand', 'Hundred million'],
        ['', 'ten', 'Hundred', 'Thousand']
    ];
    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(/Fatal Frame./, '');
    }
    s = s || 'whole';
    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(/(Fatal Frame.)*Fatal Frame $/, '').replace(/^$/, 'Fatal Frame') + unit[0][i] + s;
    }
    return s.replace(/(Fatal Frame.)*zero yuan/, 'element')
        .replace(/(Fatal Frame.)+/g, 'Fatal Frame')
        .replace(/^whole $/, 'Zero dollar integer');
};

(2) Convert numbers to Chinese numbers

export const intToChinese = (value) => {
 const str = String(value);
 const len = str.length-1;
 const idxs = ['','ten','hundred','thousand','ten thousand','ten','hundred','thousand','Hundred million','ten','hundred','thousand','ten thousand','ten','hundred','thousand','Hundred million'];
 const num = ['Fatal Frame','one','two','three','four','five','six','seven','eight','nine'];
 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] == 'ten'){
      	 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]]
     	}
    }
   });
}

5. Operation storage

(1) Storage loadstorage

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

(2) Get localStorage

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

(3) Delete localStorage

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

(4) Storage sessionStorage

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

(5) Get sessionStorage

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

(6) Delete sessionStorage

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

6. Operating cookie s

(1) Set cookie s

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

(2) Read cookie s

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) Delete cookie

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

7. Format verification

(1) verify ID number.

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

(2) Check whether Chinese is included

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

(3) whether the check is Chinese mainland encoding.

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

(4) Verify whether it is an IPv6 address

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) Check whether it is an email address

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

(6) whether the verification is mobile phone number in Chinese mainland.

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

(7) Verify whether emoji expressions are included

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;
}

8. Operation URL

(1) Get URL parameter list

export const GetRequest = () => {
    let url = location.search;
    const paramsStr = /.+\?(.+)$/.exec(url)[1]; // Will? Take out the following string
    const paramsArr = paramsStr.split('&'); // Split the string with & and save it in the array
    let paramsObj = {};
    // Save params to object
    paramsArr.forEach(param => {
      if (/=/.test(param)) { // Handle parameters with value
        let [key, val] = param.split('='); // Split key and value
        val = decodeURIComponent(val); // decode
        val = /^\d+$/.test(val) ? parseFloat(val) : val; // Determine whether to convert to number
        if (paramsObj.hasOwnProperty(key)) { // If the object has a key, add a value
          paramsObj[key] = [].concat(paramsObj[key], val);
        } else { // If the object does not have this key, create the key and set the value
          paramsObj[key] = val;
        }
      } else { // Processing parameters without value
        paramsObj[param] = true;
      }
    })
    return paramsObj;
};

(2) Check whether the URL is valid  

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) Key value pairs are spliced into URL parameters

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

(4) Modify parameters in URL

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) Deletes the parameter specified in the URL  

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,"&");
  }
}

 

9. Equipment judgment

(1) Determine whether it is a mobile or PC device

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) Determine whether it's an apple or Android mobile device  

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

(3) Determine whether it is an Android mobile device

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

(4) Determine whether it's Windows or Mac  

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) Determine whether it is a wechat / QQ built-in browser

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) Browser model and version

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
    }
}

10. Browser operation

(1) Scroll to the top of the page

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

  (2) Scroll to the bottom of the page

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

(3) Scroll to the specified element area

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

(4) Gets the height of the visual window

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) Gets the width of the visible window

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

(6) Open browser full screen

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) Exit browser full screen

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()
    }
}

11. Time operation

(1) Current time

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 + "year" + (month + 1) + "month" + date + "day " + hour + ":" + miu + ":" + sec;
}

(2) Format time

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')

12. JavaScript operation

(1) Prevent bubbling events

export const stopPropagation = (e) => { 
    e = e || window.event; 
    if(e.stopPropagation) {    // W3C method for preventing bubbling 
        e.stopPropagation(); 
    } else { 
        e.cancelBubble = true; // IE anti bubbling method 
    } 
} 

(2) Anti shake function

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) Throttling function

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) Data type judgment

export const getType = (value) => {
  if (value === null) {
    return value + "";
  }
  // Judge whether the data is a reference type
  if (typeof value === "object") {
    let valueClass = Object.prototype.toString.call(value),
      type = valueClass.split(" ")[1].split("");
    type.pop();
    return type.join("").toLowerCase();
  } else {
    // Judge whether the data is a basic data type or a function
    return typeof value;
  }
}

(5) Object deep copy

export const deepClone = (obj, hash = new WeakMap() => {
  // Date object returns a new date object directly
  if (obj instanceof Date){
  	return new Date(obj);
  } 
  //Regular object returns a new regular object directly     
  if (obj instanceof RegExp){
  	return new RegExp(obj);     
  }
  //If circular reference is used, use weakMap to solve it
  if (hash.has(obj)){
  	return hash.get(obj);
  }
  // Gets the description of all of the object's own properties
  let allDesc = Object.getOwnPropertyDescriptors(obj);
  // Traverses the properties of all keys of the passed in parameter
  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
}

 

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