1、判断两个对象是否一致

 isObjectValueEqual(a, b) {
     var aProps = Object.getOwnPropertyNames(a)
     var bProps = Object.getOwnPropertyNames(b)

     if (aProps.length != bProps.length) {
         return false
     }


     for (var i = 0; i < aProps.length; i++) {
         var propName = aProps[i]
         var propA = a[propName]
         var propB = b[propName]

        if (typeof propA === 'object') {
             if (this.isObjectValueEqual(propA, propB)) { // 递归
                 return true
             } else {
                 return false
             }
         }
        else if (propA !== propB) {
            return false
        }
        else {
        }
    }
    return true
}

2、数组去重

let arr = [1, 2, 3, 3, 2, '1', 0, 1, 2]
let newArr = [...new Set(arr)]
//  or
let newArr = Array.from(new Set(arr))

3、数组对象根据字段去重

export const uniqueArrayObject = (arr = [], key = 'id') => {
  if (arr.length === 0) return
  let list = []
  const map = {}
  arr.forEach((item) => {
    if (!map[item[key]]) {
      map[item[key]] = item
    }
  })
  list = Object.values(map)
  return list
}

4、根据某个属性排序

sortBy(attr, rev) { // 第二个参数没有传递 默认升序排列
    if (rev === undefined) {
        rev = 1
    } else {
        rev = (rev) ? 1 : -1
    }
    return function (a, b) {
        a = a[attr]
        b = b[attr]
        if (a < b || (a === null && b !== null)) {
        return rev * -1
    }
    if (a > b || (a !== null && b === null)) {
        return rev * 1
    }
        return 0
    }
}

5、判断路由是否相等

export const diff = (obj1, obj2) => {
  delete obj1.close
  var o1 = obj1 instanceof Object
  var o2 = obj2 instanceof Object
  if (!o1 || !o2) {
    /*  判断不是对象  */
    return obj1 === obj2
  }

  if (Object.keys(obj1).length !== Object.keys(obj2).length) {
    return false
    // Object.keys() 返回一个由对象的自身可枚举属性(key值)组成的数组,例如：
    // 数组返回下表：let arr = ["a", "b", "c"];console.log(Object.keys(arr)) => 0,1,2;
  }

  for (var attr in obj1) {
    var t1 = obj1[attr] instanceof Object
    var t2 = obj2[attr] instanceof Object
    if (t1 && t2) {
      return diff(obj1[attr], obj2[attr])
    } else if (obj1[attr] !== obj2[attr]) {
      return false
    }
  }
  return true
}

6、判断值是否为空

/**
 * @params val:number string boolean [] {}
 */
export function validatenull(val) {
  if (typeof val === 'string') {
    if (val.trim() === '') return true
    return false
  }
  if (typeof val === 'boolean') {
    return false
  }
  if (typeof val === 'number') {
    return false
  }

  if (val instanceof Array) { // []
    if (val.length === 0) return true
  } else if (val instanceof Object) { // [] {}
    if (JSON.stringify(val) === '{}') return true
  } else {
    if (['null',null,'undefined',undefined].includes(val)) return true
    return false
  }
  return false
}