Question

There is a function, which can read a single line from the console input (Console.ReadLine()), but I wish to read or some arbitrary number of lines, which is unknown at compile time.

Answer 1

Of course it is. Just use just read a single line (using ReadLine() or whatever else you please) at a time within either a for loop (if you know at the beginning of reading how many lines you need) or within a while loop (if you want to stop reading when you reach EOF or a certain input).

EDIT:

Sure:

while ((line = Console.ReadLine()) != null) {
    // Do whatever you want here with line
}