js 格式化金额

function formatMoney (num, option = {}) {
  option = {
    decimals: 5,
    padEnd: false,
    delimiter: ',',
    ...option
    }
  if (isNaN(num)) return num
  let numArr = (num + '').split('.')
  if (option.decimals) {
    if (numArr.length > 0) {
      num = Math.round(num * Math.pow(10,option.decimals)) / Math.pow(10,option.decimals)
      numArr = (num + '').split('.')
    }
    numArr[1] = (numArr[1] || '')
    if (option.padEnd) numArr[1] = numArr[1].toString().padEnd(option.decimals, '0')
  }
  let intVal = numArr[0].replace(/(\d{1,3})(?=(\d{3})+)/g,`$1${option.delimiter}`)
  let floatVal = numArr[1] ? `.${numArr[1]}` : '.00'
  if(floatVal.length==2){
    floatVal = floatVal+'0'
  }
  return intVal + floatVal
}