Registros de funções diárias do JS

1. O número retém duas casas decimais, reescreva o método toFixed

/**
 * @description:保留两位小数，可直接截取，可四舍五入  重置Number 的 toFixed()方法 
 * @param {Number} decimals 小数位数，默认2，最多10
 * @return {Boolean} isAddZero 不够小数位是否添0  默认不添加
 * @return {Boolean} isRounding 是否四舍五入，默认是 
 * @example 123.10293.toFixed(2,true) => 123.10
 * @Author: liuxin
 */
Number.prototype.toFixed = function (decimals = 2, isAddZero = false, isRounding = true) {
    const preNum = this;
    if (isNaN(preNum) || (!preNum && preNum !== 0)) {
        return ''
    }

    // 最多10位小数
    if (decimals > 10) {
        decimals = 10;
    }

    // 先进行四舍五入
    let num = 0;
    if (isRounding === true) {
        const decimalsNumTemp = Math.pow(10, decimals); // 取保留的小数最大整数值 如10 100 1000等
        num = Math.round(parseFloat(preNum) * decimalsNumTemp) / decimalsNumTemp;
    }

    // 默认为保留的小数点后两位
    let tempNum = Number(num)
    let pointIndex = String(tempNum).indexOf('.') + 1 // 获取小数点的位置 + 1
    let pointCount = pointIndex ? String(tempNum).length - pointIndex + 1 : 0 // 获取小数点后的个数(需要保证有小数位)
    // 小数位小于需要截取的位数
    if (pointIndex === 0 || pointCount <= decimals) {
        // 源数据为整数或者小数点后面小于decimals位的作补零处理
        if (isAddZero === true) {
            let tempNumA = tempNum
            if (pointIndex === 0) {
                tempNumA = `${tempNumA}.`
                for (let index = 0; index < decimals - pointCount; index++) {
                    tempNumA = `${tempNumA}0`
                }
            } else {
                for (let index = 0; index < decimals - pointCount; index++) {
                    tempNumA = `${tempNumA}0`
                }
            }
            return tempNumA;
        }

        return tempNum
    }
    let realVal = '';

    // 截取当前数据到小数点后decimals位
    realVal = `${String(tempNum).split('.')[0]}.${String(tempNum)
        .split('.')[1]
        .substring(0, decimals)}`

    // 判断截取之后数据的数值是否为0
    if (realVal == 0) {
        realVal = 0
    }
    return realVal
}

2. Filtro de método de filtro

/**
 * @description 过滤选项值
 * @param {Object} obj 需要判断的对象
 * @param {*} value 值
 * @param {Array[Object]} options 需过滤的选项
 * @param {String} emptyString 空字符占位
 * @param {Object} prop 对应过滤的属性 默认 {text:'text',value:'value'}
 *  {text:'',value:''}  => return text
 * @author liuxin
 */
export function filterOptions(value, options, emptyString = "", prop = {
	text: 'text',
	value: 'value'
}) {
	if (value === undefined || value === null) {
		return emptyString;
	}

	let returnValue = emptyString;
	for (const i in options) {
		if (options[i][prop.value] === value) {
			returnValue = options[i][prop.text];
			break;
		}
	}
	return returnValue;
}

3. Obter data

3.1 Obtenha o ano, mês e dia atuais

/**
 * @description: 获取当前年月日
 * @param {String} splitString 分割符号
 * @return {String} 2021-8-18
 * @Author: liuxin
 */
export function getCurrentDate(splitString = "-") {
    const date = new Date();
    const month = date.getMonth() + 1;
    const day = date.getDate();
    return date.getFullYear() + splitString +
        (month < 10 ? ('0' + month) : month) + splitString +
        (day < 10 ? ('0' + day) : day)
}

3.2 Obter o número de dias em dois períodos de tempo

/**
 * @description: 获取两个时间内的天数
 * @param {String} startTime 开始日期 2021-01-01
 * @param {String} endTime 结束日期 2021-01-01
 * @return {Number} 2021-01-01,2021-01-01 结果是1 
 * @Author: liuxin
 */
export function getDayByTwoDate(startTime, endTime) {
    if (!startTime || !endTime) {
        return null;
    }
    const startDate = new Date(startTime).getTime();
    const endDate = new Date(endTime).getTime();

    return (endDate - startDate) / 1000 / 60 / 60 / 24 + 1; // 自动加一天，从当日算起
}

4. Baixar arquivos

/**
 * @description 下载文件
 * @param {file} fileByte  字节流
 * @param {String} fileName  文件名称 
 * @example downFile(**,"测试.doc")
 * @author liuxin
 */
export function downFile(fileByte, fileName) {
    if (!fileByte) {
        return;
    }
    let url = window.URL.createObjectURL(new Blob([fileByte]));
    let link = document.createElement("a");
    link.style.display = "none";
    link.href = url;
    link.setAttribute("download", fileName);
    document.body.appendChild(link);
    link.click();
}

5. Converta o valor para letras maiúsculas

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