What really is the purpose of "base" keyword in c#?

Question

Thus for used base class for some commom reusable methods in every page of my application...

public class BaseClass:System.Web.UI.Page {    public string GetRandomPasswordUsingGUID(int length)    {       string guidResult = System.Guid.NewGuid().ToString();       guidResult = guidResult.Replace("-", string.Empty);       return guidResult.Substring(0, length);    } } 

So if i want to use this method i would just do,

public partial class forms_age_group : BaseClass {       protected void Page_Load(object sender, EventArgs e)       {             //i would just call it like this             string pass = GetRandomPasswordUsingGUID(10);       } } 

It does what i want but there is a "Base" keyword that deals with base class in c# ... I really want to know when should use base keyword in my derived class....

Any good example...

Answer 1

The base keyword is used to refer to the base class when chaining constructors or when you want to access a member (method, property, anything) in the base class that has been overridden or hidden in the current class. For example,

class A {     protected virtual void Foo() {         Console.WriteLine("I'm A");     } }  class B : A {     protected override void Foo() {         Console.WriteLine("I'm B");     }      public void Bar() {         Foo();         base.Foo();     } } 

With these definitions,

new B().Bar(); 

would output

I'm B I'm A 

Answer 2

You will use base keyword when you override a functionality but still want the overridden functionality to occur also.

example:

 public class Car  {      public virtual bool DetectHit()       {           detect if car bumped          if bumped then activate airbag       }  }    public class SmartCar : Car  {      public override bool DetectHit()      {          bool isHit = base.DetectHit();           if (isHit) { send sms and gps location to family and rescuer }           // so the deriver of this smart car           // can still get the hit detection information          return isHit;       }  }    public sealed class SafeCar : SmartCar  {      public override bool DetectHit()      {          bool isHit = base.DetectHit();           if (isHit) { stop the engine }           return isHit;      }  }