Call parent method from child class c#

Question

This is a slightly different question from previous answers I have seen or I am not getting it. I have a parent class with a method named MyMethod() and a variable public Int32 CurrentRow;

public void MyMethod()
{    
     this.UpdateProgressBar();    
}

In the parent I create a new instance of ChildClass

Boolean loadData = true;
if (loadData) 
{    
     ChildClass childClass = new ChildClass();    
     childClass.LoadData(this.Datatable);    
}

In the child Class LoadData() method I want to be able to set the CurrentRow variable of the parent and call the MyMethod() function.

How do I do this?

Answer 1

To access properties and methods of a parent class use the base keyword. So in your child class LoadData() method you would do this:

public class Child : Parent  {     public void LoadData()      {         base.MyMethod(); // call method of parent class         base.CurrentRow = 1; // set property of parent class         // other stuff...     } } 

Note that you would also have to change the access modifier of your parent MyMethod() to at least protected for the child class to access it.

Answer 2

Found the solution.

In the parent I declare a new instance of the ChildClass() then bind the event handler in that class to the local method in the parent

In the child class I add a public event handler:

public EventHandler UpdateProgress; 

In the parent I create a new instance of this child class then bind the local parent event to the public eventhandler in the child

ChildClass child = new ChildClass(); child.UpdateProgress += this.MyMethod; child.LoadData(this.MyDataTable); 

Then in the LoadData() of the child class I can call

private LoadData() {     this.OnMyMethod(); } 

Where OnMyMethod is:

public void OnMyMethod() {      // has the event handler been assigned?      if (this.UpdateProgress!= null)      {          // raise the event          this.UpdateProgress(this, new EventArgs());      } } 

This runs the event in the parent class