字段是否需要属性才能使用 get set？

Question

I'm making classes and I wanted to know the differnce in the application of the getters and setters.

eg

public class Employee
    {
       
        private string forename;
        public string Forename { get { return forename; } }
        private string surname;
        public string Surname { get { return surname; } }
        private int age;
   }

In what I have made I have 'private string forename;'. Because it doesn't have {get;set;} is it a variable instead of a field in the class? Also because it is private I have used a property with the same name in order to access forename. I guess my question is what is the point in having the separate Forename/forename if I have to write {get; set;} for the private one as well as the public one. Is there a better way to write the fields? Couldn't I just have written:

private string forename{ get { return forename; } }   

eg for my password field I have:

private string password;
        public string Password 

        { set
            {
                bool validPassword = false;
                if (value.Length > 7 & value.Length < 15)
                {
                    if (value.Any(char.IsLower))
                    {
                        if (!value.Contains(" "))
                        {
                            if (value.Any(char.IsUpper))
                            {
                                string specialChar = @"%!@#$%^&*()?/>.<,:;'\|}]{[_~`+=-" + "\"";
                                char[] specialCharArray = specialChar.ToCharArray();
                                foreach (char ch in specialCharArray)
                                {
                                    if (value.Contains(ch))
                                    {
                                        validPassword = true;
                                        Console.WriteLine("Password has been changed");
                                        break;
                                    }
                                }
                            }
                        }
                    }
                }

Couldn't I have just put this all in a {set} on the private password?

Answer 1

password is a private field, and Password is a public property.

You are correct that you could put this logic directly in the set block of the private password field.

But by using a property with a set block instead of a field with a set block, you can specify the logic for validating and assigning the password value at a single place, and you can expose the password value to other codes through the property. It makes your code easier to maintain and understand.

user can simply assign a password like this employee.Password = "@$@#%@#%@#;"; without knowing the internal details. you can also change this implementation in future without breaking anything.

In short properties are the wrapper around fields.

Forename property only has a getter, which means that it is a read-only property.

Here is the official documentation of properties, you can refer this as well.