JS bridge

JS Bridge 通信原理
https://mp.weixin.qq.com/s/T78J3dM9i5TvLu0h6joX3A

操作class

// 查询class
export const hasClass = function(obj, cls) {
  return obj.className.match(new RegExp('(\\s|^)' + cls + '(\\s|$)'));
};
// 添加class
export const addClass = function(obj, cls) {
  if (!hasClass(obj, cls)) obj.className += ' ' + cls;
};
// 移除class
export const removeClass = function(obj, cls) {
  if (hasClass(obj, cls)) {
    const reg = new RegExp('(\\s|^)' + cls + '(\\s|$)');
    obj.className = obj.className.replace(reg, ' ');
  }
};
// class切换
export const toggleClass = function(obj, cls) {
  if (hasClass(obj, cls)) {
    removeClass(obj, cls);
  } else {
    addClass(obj, cls);
  }
};

js 判断

// 判断是null or undefined or ''
export const isEmpty = function (val) {
  // null or undefined
  if (val == null) return true
  if (typeof val === 'boolean') return false
  if (typeof val === 'number') return !val
  if (val instanceof Error) return val.message === ''
  switch (Object.prototype.toString.call(val)) {
    // String or Array
    case '[object String]':
    case '[object Array]':
      return !val.length
    // Map or Set or File
    case '[object File]':
    case '[object Map]':
    case '[object Set]': {
      return !val.size
    }
    // Plain Object
    case '[object Object]': {
      return !Object.keys(val).length
    }
  }
  return false
}
export function isString(obj) {
  return Object.prototype.toString.call(obj) === '[object String]'
}
export function isObject(obj) {
  return Object.prototype.toString.call(obj) === '[object Object]'
}
export function isArray(value) {
  return value instanceof Array
}
export function isHtmlElement(node) {
  return node && node.nodeType === Node.ELEMENT_NODE
}
export const isFunction = (functionToCheck) => {
  var getType = {}
  return (
    functionToCheck &&
    getType.toString.call(functionToCheck) === '[object Function]'
  )
}
export const isUndefined = (val) => {
  // eslint-disable-next-line no-void
  return val === void 0
}
export const isDefined = (val) => {
  return val !== undefined && val !== null
}
// 是否相等
// 数组、字符串、数字(对象不行)
export const valueEquals = (a, b) => {
  // see: https://stackoverflow.com/questions/3115982/how-to-check-if-two-arrays-are-equal-with-javascript
  if (a === b) return true
  if (!(a instanceof Array)) return false
  if (!(b instanceof Array)) return false
  if (a.length !== b.length) return false
  for (let i = 0; i !== a.length; ++i) {
    if (a[i] !== b[i]) return false
  }
  return true
}