How to determine the type of an generic array element with reflection?

What I'm trying to do is without generic types simple.

SomeType[] s = new SomeType[5];
for(int i = 0; i < 5: i++){
  s[i]= new SomeType();
}

Using generics this is what I have so far.

private static T TypeMapper<T>(dynamic handle) {

    if (typeof(T).IsArray)
    {
        Type elementType = typeof(T).GetElementType();
        int arrayLength = handle.Length;
        Array array = Array.CreateInstance(elementType, arrayLength);

//???  How to get the type of an generic array element
        Type typeOfthis = typeof(array[0]).GetElementType();

        for (int i = 0; i < arrayLength; i++)
        {
//??? How to create an instance from it.
            array[i] = new typeOfthis ();
        }


        T obj = (T)(object)array;
        return obj;
    }
    else
    {}

Then calling the TypeMapper function with.

dynamic t = new TextSpan[4];
var result = TypeMapper<TextSpan[]>(t)

How can I get the type of an generic array element.

Type typeOfthis = typeof(array[0]).GetElementType();//Not Working

And how to create an instance from it.

array[i] = new typeOfthis ();

Your help is highly appreciated.