eln_web/src/utils/calUnitTools.js

//体积不同单位相加
export function addTj(valueArr, unitArr) {
  let unit = ['pL', 'nL', 'uL', 'mL', 'L']

  //计算最小单位
  let mixIndex = unit.length - 1
  for (let i = 0; i < unitArr.length; i++) {
    let thisIndex = unit.indexOf(unitArr[i])
    mixIndex = thisIndex < mixIndex ? thisIndex : mixIndex
  }

  let total = 0
  for (let i = 0; i < unitArr.length; i++) {
    let thisIndex = unit.indexOf(unitArr[i])
    total = addDecimals(
      total,
      multiplyDecimals(
        parseFloat(valueArr[i]),
        Math.pow(1000, thisIndex - mixIndex)
      )
    )
    // total += parseFloat(valueArr[i]) * Math.pow(1000, thisIndex - mixIndex)
  }
  return {
    total: total,
    unit: unit[mixIndex]
  }
}

export function addDecimals(a, b) {
  if (Number.isNaN(a) || Number.isNaN(b)) {
    return 0
  }
  const strA = a.toString()
  const strB = b.toString()

  // 获取小数位数
  const getDecimals = (str) => (str.split('.')[1] || '').length
  const maxLen = Math.max(getDecimals(strA), getDecimals(strB))

  // 相加并格式化为字符串
  const result = (parseFloat(a) + parseFloat(b)).toFixed(maxLen)

  // 去掉末尾的0
  return result.replace(/(\.\d*?)0+$/, '$1').replace(/\.$/, '')
}

export function multiplyDecimals(a, b) {
  if (Number.isNaN(a) || Number.isNaN(b)) {
    return 0
  }
  const strA = a.toString()
  const strB = b.toString()

  const decA = (strA.split('.')[1] || '').length
  const decB = (strB.split('.')[1] || '').length
  const totalDecimals = decA + decB

  const numA = BigInt(strA.replace('.', ''))
  const numB = BigInt(strB.replace('.', ''))

  const product = numA * numB
  const productStr = product.toString()

  const isNegative = productStr.startsWith('-')
  const absStr = isNegative ? productStr.substring(1) : productStr

  let result = ''
  if (totalDecimals === 0) {
    result = absStr
  } else if (absStr.length <= totalDecimals) {
    result = '0.' + absStr.padStart(totalDecimals, '0')
  } else {
    result =
      absStr.substring(0, absStr.length - totalDecimals) +
      '.' +
      absStr.substring(absStr.length - totalDecimals)
  }

  result = result.replace(/\.?0+$/, '') || '0'
  return (isNegative ? '-' : '') + result
}