I'm having trouble accessing a data from an array using the index.

I've the following code in my template.

<a href="#" class="...">{{ fixture.flatOdds.data[0].market_id }}</a>

I'm having trouble accessing a data from an array using the index.

I've the following code in my template.

<a href="#" class="...">{{ fixture.flatOdds.data[0].market_id }}</a>

And that throws:

TypeError: fixture.flatOdds.data[0] is undefined

But fixture.flatOdds.data[0] is defined. When I print out the fixture.flatOdds.data[0] like this:

<a href="#" class="...">{{ fixture.flatOdds.data[0] }}</a>

It prints out the object just fine. The response,

{ "bookmaker_id": 2, "bookmaker_event_id": null, "market_id": 1, "odds": [ { "label": "1", "value": 3, "winning": null, "handicap": null, "total": null, "last_update": { "date": "2018-07-29 08:15:53.000000", "timezone_type": 3, "timezone": "UTC" } }, { "label": "X", "value": 3.2, "winning": null, "handicap": null, "total": null, "last_update": { "date": "2018-07-29 08:15:53.000000", "timezone_type": 3, "timezone": "UTC" } }, { "label": "2", "value": 2.38, "winning": null, "handicap": null, "total": null, "last_update": { "date": "2018-07-29 08:15:53.000000", "timezone_type": 3, "timezone": "UTC" } } ] }

What am I doing wrong?

Note: I am using axios to load the data from an API.

• javascript
• vue.js
• vuejs2

2 Answers 2

The problem most likely is that the value is undefined at some point in the ponents lifecycle (you're probably loading it asynchronously). You are going to need be be defensive in the way that you reference your property.

You could use a puted property

const ponent = {
  puted: {
    marketId () {
      if (this.fixture && this.fixture.flatOdds && this.fixture.flatOdds.data) {
        return fixture.flatOdds.data[0].market_id
      }
      return 'unknown'
    }
  }
}

Or you could also use a filter,

<template>
  <span>{{fixture | getMarketId}}</span>
</template>

<script>
export default {
  filter: {
    getMarketId (obj) {
      if (obj && obj.flatOdds && obj.flatOdds.data) {
        return obj.flatOdds.data[0].market_id
      }
      return 'unknown'
    }
  }
}
</script>

Or as per @ittus's example use a v-if, but just be careful of which part of your object is undefined.

Are you loading data asynchronously? fixture.flatOdds.data[0] might not be available when data is not loaded.

You can add v-if to check if data is available.

   <a href="#" class="..." 
     v-if="fixture.flatOdds.data[0]">
     {{ fixture.flatOdds.data[0].market_id }}
   </a>