Question mark and colon in statement. What does it mean?

Question

What do the question mark (?) and colon (:) mean?

((OperationURL[1] == "GET") ? GetRequestSignature() : "")
         


        

Answer 1

string requestUri = _apiURL + "?e=" + OperationURL[0] + ((OperationURL[1] == "GET") ? GetRequestSignature() : "");

can be translated to:

string requestUri="";
if ((OperationURL[1] == "GET")
{
    requestUri = _apiURL + "?e=" + GetRequestSignature();
}
else
{
   requestUri = _apiURL + "?e=";
}