WRite factorial program in C#? code example

Example: factorial of a given number in c

//Factorial of a given number
#include <stdio.h>

//This function returns factorial of the number passed to it 
long int factorialOf(int number){
    long int factorial = 1;
    while(number){
        factorial*=number;
        number-=1;
    }
    return factorial;
}

int main(void) {
	int n;
	printf("Find factorial of \n");
	scanf("%d",&n);
	printf("\nThe factorial of %d is %ld",n,factorialOf(n));
	return 0;
}