Filter
Top Products
Chapter 3: Learning Just Enough C# and VB.NET: Types and Members 81
Coding Fields and Properties
A field is a variable that is a member of a class (type), as opposed to variables that are
declared inside of methods, which are called local variables or locally scoped variables.
Properties are type members that give you functionality that is a cross between fields and
methods. You can read and write to a property just as you can to a field. Additionally,
you can define code that runs whenever you read to or write from a property, similar to
methods. The following sections define fields and properties.
Declaring and Using Fields
As stated, a field is a variable that is a member of a class (or some other container, such
as a struct, which is very similar to a class). This provides the benefit of having the
field and the data it contains available to all of the other members of the class (as well
as to any deriving classes, via inheritance, depending on the field’s access modifier).
To
demonstrate how a field is declared and used, the example in Listing 3-8 simulates a bank
account that has a field of type decimal named currentBalance, which holds an account
balance. The class has two methods: Credit and Debit. Credit increases the value of
currentBalance, and Debit decreases the value of currentBalance.
Listing 3-8 Using fields and properties
C#:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace FirstProgram
{
class Program
{
private decimal accountBalance = 100m;
static void Main(string[] args)
{
Program account = new Program();
account.Credit(100m);
account.Debit(50m);
Console.WriteLine("Balance: " + account.CurrentBalance);
Console.ReadKey();
}