Object.length undefined in javascript [duplicate]

Answer 1

coordinates is an object. Objects in javascript do not, by default, have a length property. Some objects have a length property:

"a string - length is the number of characters".length

['an array', 'length is the number of elements'].length

(function(a, b) { "a function - length is the number of parameters" }).length

You are probably trying to find the number of keys in your object, which can be done via Object.keys():

var keyCount = Object.keys(coordinates).length;

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Be careful, as a length property can be added to any object:

var confusingObject = { length: 100 };