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ElementExists (array, key)

Result type:  Boolean (0, or 1)

Definition:  Returns true if an element with the given key exists in the array. Returns false if no element with the key exists.

Example:  

let a = CreateArray();
let a["key1"] = 5
let a["key2"] = "foo"
alert(ElementExists(a, "key1")) // displays 1
DeleteElement(a, "key1")
alert(ElementExists(a, "key1")) // displays 0

Availability:  available within MWScript handlers.

See Also:

CountElements: Get the size of an associative array

CreateArray: Create an empty associative array

DeleteElement: Remove a key from an associative array

ParamsFromArray: Expand array values to a variable parameter list

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