System.NotImplementedException

Namespace: System

❓Summary

Represents errors that occur during execution when a requested method or operation is not implemented.

📜Description

The NotImplementedException class is used to indicate that a requested operation has not been implemented. This exception is typically thrown by methods or properties that have not yet been fully developed or are not intended to be supported. It's a common placeholder during the development process to signal incomplete functionality.

When NotImplementedException is thrown, it signals a problem in the program's logic or design, indicating that the caller attempted to access functionality that is not yet available.

📦Inheritance

🛠️Constructors

Constructor Description
NotImplementedException() Initializes a new instance of the NotImplementedException class with a default message.
NotImplementedException(string message) Initializes a new instance of the NotImplementedException class with a specified message.
NotImplementedException(string message, Exception innerException) Initializes a new instance of the NotImplementedException class with a specified message and a reference to the inner exception that is the cause of this exception.

💡Usage Example

Here's a simple example demonstrating how NotImplementedException might be used in a class that is still under development: 


public class Shape
{
    public virtual double GetArea()
    {
        throw new NotImplementedException("The GetArea method is not implemented for the base Shape class.");
    }

    public virtual double GetPerimeter()
    {
        throw new NotImplementedException("The GetPerimeter method is not implemented for the base Shape class.");
    }
}

public class Circle : Shape
{
    public double Radius { get; set; }

    public override double GetArea()
    {
        // Area calculation for a circle
        return Math.PI * Radius * Radius;
    }

    // GetPerimeter is not yet implemented for Circle
    // public override double GetPerimeter() { ... }
}

// --- In another part of the application ---
try
{
    Shape myShape = new Circle { Radius = 5 };
    // Calling GetPerimeter on a shape where it's not implemented will throw the exception
    double perimeter = myShape.GetPerimeter();
    Console.WriteLine($"Perimeter: {perimeter}");
}
catch (NotImplementedException ex)
{
    Console.WriteLine($"Error: {ex.Message}");
    // Handle the situation, perhaps log the error or inform the user.
}

🔗See Also