yylib-quick-mobile/dist/utils/MathUtils.js

yylib-quick-mobile

import uuid from 'uuid';

let MathUtils = {
    uuid: () => {
        let uuidArr = uuid.v4().split("-");
        return uuidArr.join("");
    },

    /**
     * 通过移动小数点  扩大倍数或缩小倍数(解决出现e+、e-的问题)
     *
     * @param value 数字字符串
     */
    scienceNum: function (value) {
        if (!value) return value;
        if (typeof value === 'number') value = value + "";
        let minusStr = '';//是否有负号，例如：-5e-8、-2.3e-8
        if (value.substring(0, 1) === '-') {
            minusStr = '-';
            value = value.substring(1, value.length);
        }
        let eIndex = value.indexOf('E');
        if (eIndex == -1) eIndex = value.indexOf('e');
        if (eIndex != -1) {
            let doubleStr = value.substring(0, eIndex);
            let eStr = value.substring(eIndex + 1, value.length);
            eStr = parseInt(eStr);
            let doubleStrList = doubleStr.split('.');
            let doubleStr1 = doubleStrList[0] || "";
            let doubleStr2 = doubleStrList[1] || "";

            if (eStr < 0) {  //e- 很小的数
                let str1Len = doubleStr1.length;
                let eStrs = Math.abs(eStr);
                if (str1Len > eStrs) {
                    let nums = doubleStr1.substring(0, eStrs);
                    let nume = doubleStr1.substring(eStrs, str1Len);
                    doubleStr = nums + "." + nume + nume;
                } else if (str1Len < eStrs) {
                    let indexNum = eStrs - str1Len;
                    let str = _makeZero(indexNum); //用0补齐
                    doubleStr = '0.' + str + doubleStr1 + doubleStr2;
                } else {
                    doubleStr = '0.' + doubleStr1 + doubleStr2;
                }
            } else { //e+ 很大的数
                let str2Len = doubleStr2.length;
                if (str2Len > eStr) {
                    let nums = doubleStr2.substring(0, eStr);
                    let nume = doubleStr2.substring(eStr, str2Len);
                    doubleStr = doubleStr1 + nums + '.' + nume;
                } else if (str2Len < eStr) {
                    let indexNum = eStr - str2Len;
                    let str = _makeZero(indexNum); //用0补齐
                    doubleStr = doubleStr1 + doubleStr2 + str;
                } else {
                    doubleStr = doubleStr1 + doubleStr2;
                }
            }
            value = doubleStr;
        }
        return minusStr + value;
    }
};

export default MathUtils;