vue常见数值处理封装

参考：https://juejin.cn/post/6844903951876227080
js：

//保留n位小数并格式化输出（不足的部分补0）
var fomatFloat = function(value, n) {
    var f = Math.round(value*Math.pow(10,n))/Math.pow(10,n)
    var s = f.toString();
    var rs = s.indexOf('.')  
    if (rs < 0) {     
        s += '.'
    } 
    for(var i = s.length - s.indexOf('.'); i <= n; i++){
      s += "0"
    }
    return s
}

TS:

/**
 *
 * @param value 处理值
 * @param fixed 精确到小数点后位数，不足补0
 * @returns
 */
export function NumberSplitByComma(value: string | number, fixed = 0): string {
  if (value === undefined || value === '') {
    return '0';
  }
  let ret = '';
  const str = value.toString();
  if (str.indexOf('.') !== -1) {
    let [a, b] = str.split('.');
    a = a.replace(/(\d)(?=(?:\d{3})+$)/g, '$1,');
    if (b.length > fixed) {
      b = b.slice(0, fixed);
    } else {
      b = b.padEnd(fixed, '0');
    }
    ret = `${a}.${b}`;
  } else {
    ret = str.replace(/(\d)(?=(?:\d{3})+$)/g, '$1,');
    if (fixed) {
      ret = `${ret}.`;
      ret = ret.padEnd(ret.length + fixed, '0');
    }
  }
  return ret;
}

/**
 *
 * @param value 处理值
 * @param fixed 四舍五入到小数点后位数，不足补0,
 * @returns
 */
export function formatNumber(value: string | number, fixed = 2): string {
  if (!value) {
    return `0.${''.padEnd(fixed, '0')} `;
  }
  let budget = (+value).toFixed(fixed);
  budget = NumberSplitByComma(budget, fixed);
  return budget;
}