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

User · Answer

To follow up on the comment by suhendri to Rory McCrossan answer. Here is an Action delegate example:

In child add:

public Action UpdateProgress;  // In place of event handler declaration
                               // declare an Action delegate
.
.
.
private LoadData() {
    this.UpdateProgress();    // call to Action delegate - MyMethod in
                              // parent
}

In parent add:

// The 3 lines in the parent becomes:
ChildClass child = new ChildClass();
child.UpdateProgress = this.MyMethod;  // assigns MyMethod to child delegate

User · Answer

One way to do this would be to pass the instance of ParentClass to the ChildClass on construction  public ChildClass       private ParentClass parent       public ChildClass ParentClass parent                this parent   parent             public void LoadData DateTable dt                  do something        parent CurrentRow       or whatever         parent UpdateProgressBar       Call the method           Make sure to pass the reference to this when constructing ChildClass inside parent   if loadData         ChildClass childClass   new ChildClass this      here       childClass LoadData this Datatable        Caveat  This is probably not the best way to organise your classes  but it directly answers your question   EDIT  In the comments you mention that more than 1 parent class wants to use ChildClass  This is possible with the introduction of an interface  eg   public interface IParentClass       void UpdateProgressBar        int CurrentRow get  set       Now  make sure to implement that interface on both  all   Parent Classes and change child class to this   public ChildClass       private IParentClass parent       public ChildClass IParentClass parent                this parent   parent             public void LoadData DateTable dt                  do something        parent CurrentRow       or whatever         parent UpdateProgressBar       Call the method           Now anything that implements IParentClass can construct an instance of ChildClass and pass this to its constructor

User · Answer

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

User · Answer

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

[c#] Call parent method from child class c#

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