[Vuejs]-Array undefined javascript

Emit the event after you recieve the data:

check_ref_number: function () {
 axios.get('/is_referenceNumber_free/'+this.ref_number)
 .then(response => Event.$emit('reference_added',[{info:response.data}]));
}

The problem is that you are getting the data asynchronously, and trying to use the data before it is ready.

You said you are trying to access the the array length, but

this.ref_number_response

is the array, so the only way this console.log(this.ref_number_response[0].info.length); is going to work ( you’re trying to get the info property from first element of the array length not the actual array length ) is if info were an array as well. So you’d probably need to do something like:

console.log(this.ref_number_response.length);