Javascript's array of undefined values

My issue is that I am receiving an "undefined" error when trying to access the array length. However, everything works fine when I try to access only the array itself.

The following does not work ->

console.log(this.ref_number_response[0].info.length);

This works ->

console.log(this.ref_number_response);

And here is the complete code:


check_ref_number: function () {

 this.ref_number_response = [];

 axios.get('/is_referenceNumber_free/'+this.ref_number)
 .then(response => this.ref_number_response.push({ 
   info: response.data

}));


 console.log(this.ref_number_response[0].info.length);

 Event.$emit('reference_added', this.ref_number_response);

},

Answer №1

Make sure to trigger the event only after receiving the data:

validate_reference_number: function () {
 axios.get('/check_if_ref_number_available/'+this.reference_num)
 .then(response => Event.$emit('reference_validated',[{details:response.data}]));
}

The issue arises when attempting to utilize the data before it has been fully retrieved due to its asynchronous nature.

Answer №2

When attempting to access the length of the array, it's important to note that

this.ref_number_response

represents the array itself. In order for

console.log(this.ref_number_response[0].info.length);
to function correctly (in this case, extracting the length property from the first element of the array rather than the overall array length), 'info' would need to be an array as well. To achieve this, you might need to modify your code like so:

console.log(this.ref_number_response.length);

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