isNull (target) {    if (typeof (target) === 'undefined' || target === null || target === '' || target === 'null' || target === 'undefined') {      return true    } else {      return false    }  }/**   * 加法运算   *   * @param arguments 加数入参，个数不定   * @returns 和   */  adds () {    let result = 0    let arrLength = []    let r1, m    for (let item in arguments) {      arguments[item] = this.isNull(arguments[item]) ? 0 : arguments[item]      try {        r1 = arguments[item].toString().split('.')[1].length      } catch (e) {        r1 = 0      }      arrLength.push(r1)      result += arguments[item]    }    m = Math.pow(10, Math.max.apply(null, arrLength))    return (result * m) / m  }

 

使用说明：

adds(RC1, RC2)