Скачать или смотреть How to Properly Define the Number of Different Objects to Create in C#

Discover how to effectively manage the creation of diverse object instances in C# using user-defined counts. This guide will guide you through the process step-by-step!
---
This video is based on the question https://stackoverflow.com/q/64636997/ asked by the user 'Gus Evan' ( https://stackoverflow.com/u/14560168/ ) and on the answer https://stackoverflow.com/a/64637729/ provided by the user 'Rod Ramírez' ( https://stackoverflow.com/u/9667085/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: How can I properly define the number of different objects to create?

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
How to Properly Define the Number of Different Objects to Create in C#

In the realm of programming, especially when dealing with object-oriented languages like C# , managing the creation of multiple instances of different object types can present a challenge. Developers often need to create a specific number of objects based on user input, which can become a complex task if not structured correctly. In this guide, we'll explore how to handle this situation effectively by defining a method that allows us to create a desired quantity of various objects such as Employee, Manager, and Recruiter.

Understanding the Problem

Imagine you're tasked with designing a system that needs to create different types of personnel objects based on user preferences. For example, a user might want to have:

Two Employees

One Manager

Zero Recruiters

The challenge arises in dynamically creating these objects in a structured manner, ensuring that the exact number specified by the user is instantiated and added to a list.

A Practical Solution

To solve this problem, we can modify the CreatePersonInstances method within our class to accept parameters for the number of each type of object to create. Here's how we can achieve this:

Step 1: Updating the Method Signature

First, we'll need to update the CreatePersonInstances method to accept integer parameters for each type of person we want to create. Here's a revised version of the method:

[[See Video to Reveal this Text or Code Snippet]]

Step 2: Explanation of the Code

Input Validation: We start with a validation step to ensure that the numbers provided by the user are non-negative. This prevents any unexpected behavior when trying to instantiate objects.

Dynamic Object Creation: By utilizing Enumerable.Range, we generate a range of integers (from 0 up to the specified count). The Select method then maps each integer to a new instance of the respective class (Employee, Manager, or Recruiter).

AddRange Method: Finally, we use AddRange to add the generated collections of objects directly into our ExampleList.

Step 3: The Person Class Hierarchy

In our implementation, Employee, Manager, and Recruiter classes will inherit from a base class called Person. Here’s how they might look:

[[See Video to Reveal this Text or Code Snippet]]

Beyond the Basics: Factory Design Pattern

This approach not only solves the problem of instantiating various objects based on user-defined quantities but also serves as an excellent use case for the Factory Design Pattern. In scenarios where the instantiation of objects becomes more complex or requires additional setup, leveraging a factory can help manage this process efficiently and improve code maintainability.

Conclusion

Defining the number of different objects to create in C# can be straightforward with the right approach. The method we outlined ensures that you can easily create the precise number of specified personnel types, demonstrating both flexibility and control. As your application grows, consider employing design patterns like the Factory pattern to further streamline your object creation process. Happy coding!