How send How send params to setup?

I have ethernet shield. I want pass ip param from c# code to arduino. I understand how i can params to loop, but cannot understand how to pass it to setup.

RadHerber:
I understand how i can params to loop,

Good.

So just do it (whatever 'i can params' means) in loop, just once.

void loop() {

static bool IDidIt;

  if (!IDidIt) {
    IDidIt = true;
    // .....
  }
}

Everything that you can do in loop() can be done in setup(), too. The main difference is the loop() runs over and over, and your code for getting data in loop() most likely does NOT get all the data in one iteration of loop.

So, you’ll need to set up some kind of while(!gotAllTheData) {} loop in setup() to make it behave like loop(), until all the data has arrived.

Or, to "merge" the two ideas in Replies #1 and #2, put the repeating code as the first thing in loop() and don't let the program go further until the data has been received.

...R