无法读取未定义的属性，正在寻找对象属性

Question

I am trying to get the dots array from each object. However I keep getting cannot read property dots of undefined.

 let events = fetchEvents[this.state.selectedDay || selected];

in my component I am using:

      <EventCalendar
         events={events.dots || []} 
...

I'm my EventCalendar component, this.props.events is undefined

  render() {
    const {
      width,
      virtualizedListProps,
      initDate,
      formatHeader,
      upperCaseHeader = false
    } = this.props;

    const allDayEvents = this.props.events.filter(
      event => event.allDayEvent == 1
    );

fetchEvents array:

  2019-03-06: {dots: Array(2), disabled: false, selected: true, selectedColor: "#00CCCB", customStyles: {…}}
    2019-03-07: {dots: Array(1), disabled: false, selected: true, 

Answer 1

I believe you're not calling the intended JSON Object. Have you tried events['2019-03-07'].dots? Side Note: I would not use the date with a hyphen as your key. You could remove the hyphen just to have digits instead since each key will be unique. Please refer to image below.