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I ask because when you find yourself trying to circumvent one of the most basic characteristics of a programming language, odds are good there's a better way to do what you're trying to do. It would help to know what your AJAX request looks like. I want to create an array whose indexing starts from 1 instead. The following example illustrates this behavior. It's not like an array where you can access a value by index ("pick the first value"). Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. JavaScript arrays are zero based, which means the first item is referenced with an index of 0. As we saw, arrays can have several dimensions, which means that an array element can contain an array, whose elements can contain arrays, etc. let arr = Array (9.3) // RangeError: Invalid array length. Here’s an example of an indexed array: Here’s an example of … So we eventually get: It sounds like the data structure is confusing :-) If you have an object with unknown/random property names, you can't really access a specific property without knowing the name. Remember that the index values start at 0, not 1. An “indexed” array is one where the index must be an integer, and you access its elements using its index as a reference. So, our array of four elements has indexes from 0 to 3. Referencing items in arrays is done with a numeric index, starting at zero and ending with the array length minus 1. I recommend using $.ajax() and specifying the dataType as JSON, or using $.getJSON(). The syntax to access an array member The Basic For Loop. The problem most likely is that the value is undefined at some point in the components lifecycle (you're probably loading it asynchronously). In the above example, we removed seahorse from the array, and pushed a new value into index 3. This means that array indexes start at 0 and go up to the number of elements, minus 1. Here is an example that demonstrates $.ajax() and shows you how to access the returned values in an array. By default the indexing of every JavaScript array starts from 0. As we can see data is an object, hence we can access its properties using dot notation. The items property is accessed as follows: data.items The value is an array, to access its second element, we have to use bracket notation: data.items[1] This value is an object and we use dot notation again to access the name property. Creating an Array Using an array literal is the easiest way to create a JavaScript Array. Calling Array(N) results in a RangeError, if N is a non-whole number whose fractional portion is non-zero. JavaScript for loops iterate over each item in an array. You could use a computed property You are going to need be be defensive in the way that you reference your property. 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