Undefined Array Elements

When is an array element not an array element? When it has never been used or initialized. ColdFusion expands arrays dynamically and as needed. So if you assign a value to array[2] after you create the array, ColdFusion will create elements 1 and 2 for you. But only element 2 will be a valid useable element. If you try to access (or even do an IsDefined()) on element 1 CF will throw an error. For this reason it is good practice to always initialize array elements with some value (perhaps “”). (Applies to: ColdFusion All)

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