Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
How can we return null from a generic method in C#?
Generics allows us to define a class with placeholders for the type of its fields, methods, parameters, etc. Generics replace these placeholders with some specific type at compile time. A generic can be defined using angle brackets <>. A primary limitation of collections is the absence of effective type checking. This means that you can put any object in a collection because all classes in the C# programming language extend from the object base class.
Also, we cannot simply return null from a generic method like in normal method. Below is the error that a generic method will throw if we are trying to return null.
using System;
namespace DemoApplication {
class Program {
public static void Main() {
Add(5, 5);
}
public static T Add<T>(T parameter1, T parameter2) {
return null;
}
}
}
So, to return a null or default value from a generic method we can make use default(). default(T) will return the default object of the type which is provided.
Example
using System;
namespace DemoApplication {
class Program {
public static void Main() {
Add(5, 5);
Console.ReadLine();
}
public static T Add<T>(T parameter1, T parameter2) {
var defaultVal = default(T);
Console.WriteLine(defaultVal);
return defaultVal;
}
}
}Output
The output of the code is
0
Here we could see that the default value of integer 0 is returned.
2K+ Views
