实现 qs.stringify 和 qs.parse 方法

/**
 * 目前支持 2 个方法，需要再扩展
 */
export const stringify = (obj = {}) => {
  const isNullOrUndefined = val => {
    return [null, undefined].includes(val)
  }
  Object.keys(obj).forEach(key => {
    if (isNullOrUndefined(obj[key])) {
      delete obj[key]
    }
  })
  return Object.keys(obj).map(key => {
    const val = obj[key]
    if (val instanceof Array) {
      if (val.length) {
        return val.map((v, index) => {
          return [`${key}[${index}]`, v].join('=')
        }).join('&')
      } else {
        return ''
      }
    }
    return [encodeURIComponent(key), encodeURIComponent(obj[key])].join('=')
  }).filter(val => val.length).join('&')
}
export const parse = (str = '') => {
  const obj = {}
  str.split('&').forEach(itemStr => {
    const itemArr = itemStr.split('=')
    obj[decodeURIComponent(itemArr[0])] = decodeURIComponent(itemArr[1])
  })
  return obj
}
export default  {
  stringify,
  parse
}

本文地址：https://www.tides.cn/p_js-qs