What method checks if an array contains a certain value in Avaloq Script?

In Avaloq Script, the method that checks if an array contains a certain value is the 'indexOf(value)' function. This method returns the first index of the specified value in the array, or -1 if the value is not found. This is particularly useful for checking presence because it provides a clear indication of whether the value exists within the array or not.

Using 'indexOf(value)', you can quickly determine if the value is part of the array by checking if the return value is greater than or equal to 0. If it is, that means the value exists. If it's -1, it indicates that the value is absent. This makes 'indexOf' an effective way to validate the inclusion of an item in an array.

The other options, while they may seem relevant, do not correspond to the correct method used for this purpose within Avaloq Script. Each of those alternatives either doesn't exist in the language or serves a different function, which makes 'indexOf(value)' the appropriate choice for this question.