Typecasting objects to doubles

So I've got an array of objects that return a number of seconds based upon a SQL query.

Code:

static ArrayList returnValueArray3 = new ArrayList();

I want to convert the values in this arrray through a method that will convert it into an easy to read format. (something like hrs/min/sec or something like that.)

I tried using this, and similiar methods:

Code:

TimeSpan.FromSeconds(returnValueArray3[i])

the problem is that I have an array of objects and I need to cast them to something like a double. I've tried several things to try and cast, but nothing has worked.

 

TimeSpan.FromSeconds(double.parse(returnValueArray3))