Vfrdtyky

I'm having a basic problem with my school code here. The code needs to ask user input as a console program, but I need it to repeat the question when entered an empty field before proceeding. So far I've tried a lot of while-loops, !isStringNullorEmpty, string.lengths, tried to create a function that checks it and some if-statements. I can't get it to work on either one of these. The program proceeds to the end all of the time.

System.Console.Write("Give first name");

String firstname = System.Console.ReadLine();



System.Console.Write("Give last name");

String lastname = System.Console.ReadLine();



System.Console.Write("Give date of birth");

DateTime = dt = DateTime.Parse(System.Console.ReadLine();

You could try

string firstName = null;

Console.WriteLine("Give first name");

while(string.IsNullOrWhiteSpace(firstName = Console.ReadLine()))

  Console.WriteLine("OMG you had one job as a user of this application, to put in the right value!");

You can do the same for DateTime

Console.Write("Give date of birth");

while (!DateTime.TryParse(Console.ReadLine(),out var dob))

    Console.Write("OMG you had one job as a user of this application, to put in the right value!");

Additional Resources

DateTime.TryParse Method

Converts the specified string representation of a date and time to its
DateTime equivalent and returns a value that indicates whether the
conversion succeeded.

you can write

   System.Console.Write("Give first name");

   String firstname = null;

   while(firstname==null || firstname==""){

       firstname = System.Console.ReadLine();

   }

Try this:

String lastname = null;



Console.Write("Give last name: ");



while (!String.IsNullOrEmpty(lastname)) {

    lastname = System.Console.ReadLine();

}

Try this

            var firstname = string.Empty;

            var lastname = string.Empty;

            var dt = DateTime.MinValue;

            do

            {

                System.Console.Write("Give first name");

                 firstname = System.Console.ReadLine();



            } while (string.IsNullOrEmpty(firstname));

            do

            {

                System.Console.Write("Give last name");

                 lastname = System.Console.ReadLine();

            } while (string.IsNullOrEmpty(lastname));





            do

            {

                System.Console.Write("Give date of birth");

                 dt = DateTime.Parse(System.Console.ReadLine());

            } while (dt != DateTime.MinValue);

try this

        bool value = true;



        while (value==true)

        {

            System.Console.Write("Give first name");

            String firstname = System.Console.ReadLine();

            if (firstname == "")

            {

                value = false;

                break;

            }

            System.Console.Write("Give last name");

            String lastname = System.Console.ReadLine();

            if (lastname == "")

            {

                value = false;

                break;

            }

            System.Console.Write("Give date of birth");

             DateTime dt = DateTime.Parse(System.Console.ReadLine());

            if (dt.ToString()=="")

            {

                value = false;

                break;

            }

        }