js返回两个数组差异值

  let arr = [
    { messageId: 1154198777724319, appid: "xiniv2", bussType: 1, type: 2},
    { messageId: 1154247598220693, ppid: "xiniv2", bussType: 1,  type: 2},
    { messageId: 1154247598222223, appid: "xiniv2", bussType: 1, type: 2},
    { messageId: 1154247598222224, appid: "xiniv2", bussType: 1, type: 2},
    { messageId: 1154247598222225, appid: "xiniv2", bussType: 1, type: 2}
  ]
  let arr2 = [
    {"messageId":1154198777724319,"unread":true},
    {"messageId":1154247598220693,"unread":true}
    ]
  let arr3 = []
  var tempArray1 = [];//临时数组1
  var tempArray2 = [];//临时数组2

  for(var i=0;i    tempArray1[arr2[i].messageId]=true;//将数array2 中的元素值作为tempArray1 中的键，值为true；
  }
  for(var i=0;i    if(!tempArray1[arr[i].messageId]){
      tempArray2.push(arr[i]);//过滤array1 中与array2 相同的元素；
    }
  }