C# Default Parameter Value

C# Default Parameter Value

In C#, a default parameter value allows you to assign a value to a method parameter so that the caller can omit that argument when calling the method.

🔹 Basic Example

Calling the Method

🔹 Multiple Default Parameters

🔹 Default Values Must Be Last

❌ Invalid:

✔ Correct:

🔹 Default Parameters with Named Arguments

🔹 Default Values and Method Overloading

Instead of writing multiple overloads:

You can use default values:

🔹 Allowed Default Values

✔ Constant values
✔ null
✔ default(type)

🔹 Common Mistakes

❌ Default parameters not at the end
❌ Using non-constant expressions
❌ Conflicts with method overloading

🔹 Summary

✔ Default values make parameters optional
✔ Must be placed at the end
✔ Work well with named arguments
✔ Reduce method overloads