I want an error to appear when the client writes a symbol or a letter
int n = 0;
string ent;
ent = Console.ReadLine();
n = int.Parse(ent);
if (n.GetType() != typeof(int)) {
Console.WriteLine("Must be a number");
}
Take a look at the official docs and the example usage:
Either wrap the int.Parse
in a try-catch block as suggested in the official docs or use int.TryParse()
here.
Try catch example:
int n = 0;
string ent;
ent = Console.ReadLine();
try {
n = int.Parse(ent);
} catch (FormatException) {
Console.WriteLine("{0}: Must be a number", ent);
}