When we are creating a Production Level Class, then any class can have thousands of Lines of Codes. So when we define a class in a single C# file, then our file can be very big. Also, when we create a class, there are often many such codes, which can be ignored once implemented. That is, there is no need to check those codes ever again.
Therefore, in C#, there has been a provision of Contextual Keyword named Partial, using which we can split a class into more than one C# Files and keep the less modified members separate from the more modified members. You can manage and maintain the Production Class in a better way.
It is necessary to specify the partial class combination with every Partial Class. The definition of a Partial Class is the same as that of a Normal Class. The only difference is that in Partial Class an extra partial word has been used.
Syntax
partial class Person
{
// Data Members
//Methods
partial datatype function_name(arguments); // function prototype
}
Example
using System;
namespace CSharpClass
{
partial class MyClass // Declaring partial class
{
partial void PrintSum(int x, int y); // Declaring partial method (Prototype)
public void Add(int x, int y)
{
PrintSum(x, y);
}
}
partial class MyClass
{
partial void PrintSum(int x, int y) // Implementing partial method (Definition)
{
Console.WriteLine('Sum is {0}', x + y);
}
}
public class Program
{
static void Main()
{
MyClass myObj = new MyClass();
myObj.Add(15, 5);
}
}
}
Output:
Sum is 20
