Question

我在angularjs中有以下代码，但是当我想要我的数组0位置的长度时，它显示未定义请检查下面的代码，这就是为什么我的第二个循环不运行。在角度如何解决这类问题，请任何人帮助我

        this.current_engineer = response.data;
              var current_schedules = this.current.schedule;
              console.log(current_schedules);
              console.log(current_schedules.length);
              console.log(current_schedules[0].length);

            if (angular.isArray(current_schedules)) {
               for (var j = 0; j < current_schedules.length; j++) {

              for (var i = 0; i < current_schedules[j].length; i++) //this loop does not run because of length how to get length
    {
              console.log(current_schedules[j][i].title);

              }
               }
            }
///------------Mongodb Database-----------------------
 "schedule" : [ 
        [ 
            {
                "_id" : ObjectId("58f76aa9be4d311a78f24f78"),
                "sch_end" : ISODate("2017-04-21T00:00:00.000Z"),
                "sch_start" : ISODate("2017-04-21T00:00:00.000Z"),
                "available" : false,
                "title" : "test3"
            }, 
            {
                "_id" : ObjectId("58f76aa9be4d311a78f24f77"),
                "sch_end" : ISODate("2017-04-22T00:00:00.000Z"),
                "sch_start" : ISODate("2017-04-22T00:00:00.000Z"),
                "available" : false,
                "title" : "test4"
            }, 
            {
                "_id" : ObjectId("58f76aa9be4d311a78f24f76"),
                "sch_end" : ISODate("2017-04-23T00:00:00.000Z"),
                "sch_start" : ISODate("2017-04-23T00:00:00.000Z"),
                "available" : false,
                "title" : "test6"
            }
        ], 
        [ 
            {
                "_id" : ObjectId("58f76aa9be4d311a78f24f78"),
                "sch_end" : ISODate("2017-04-24T00:00:00.000Z"),
                "sch_start" : ISODate("2017-04-24T00:00:00.000Z"),
                "available" : false,
                "title" : "test9"
            }, 
            {
                "_id" : ObjectId("58f76aa9be4d311a78f24f77"),
                "sch_end" : ISODate("2017-04-25T00:00:00.000Z"),
                "sch_start" : ISODate("2017-04-25T00:00:00.000Z"),
                "available" : false,
                "title" : "test10"
            }, 
            {
                "_id" : ObjectId("58f76aa9be4d311a78f24f76"),
                "sch_end" : ISODate("2017-04-27T00:00:00.000Z"),
                "sch_start" : ISODate("2017-04-27T00:00:00.000Z"),
                "available" : false,
                "title" : "test11"
            }
        ]
    ],

Answer 1

您的属性current_schedules[0]处的值是一个js对象，而js对象没有任何名为length的属性。您可以使用类似Object.keys(current_schedules[0]).length的内容。

注意：适用于IE9 +和所有其他支持ES5 +的现代浏览器。

如何获取angularjs中的长度因为长度我的第二个循环没有运行

1 个答案: