static void Main(string[] args)
{
// Passing ref-types by value.
Console.WriteLine("***** Passing Person object by value *****");
Person fred = new Person("Fred", 12);
Console.WriteLine("]nBefore by value call, Person is:");
fred.Display();
SendAPersonByValue(fred);
Console.WriteLine("\nAfter by value call, Person is:");
fred.Display();
// Passing ref-types by reference.
Console.WriteLine("\n***** Passing Person object by reference *****");
Person mel = new Person("Mel", 23);
Console.WriteLine("Before by ref call, Person is:");
mel.Display();
SendAPersonByReference(ref mel);
Console.WriteLine("After by ref call, Person is:");
mel.Display();
Console.ReadKey();
}
static void Main(string[] args)
{
// Passing ref-types by ref.
Console.WriteLine("***** Passing Person object by reference *****\n");
Person mel = new Person("Mel", 23);
Console.WriteLine("Before by ref call, Person is:");
mel.Display();
SendAPersonByValue(mel);
Console.WriteLine("After value call.");
mel.Display();
SendAPersonByReference(ref mel);
Console.WriteLine("After by ref call, Person is:");
mel.Display();
Console.ReadLine();
}
static void Main(string[] args)
{
Console.WriteLine("Passing a class by value");
Person fred = new Person("Fred", 12);
Console.WriteLine("Before pass by val: ");
fred.Display();
SendAClassByValue(fred);
Console.WriteLine("After pass by val");
fred.Display();
SendAClassByReference(ref fred);
Console.WriteLine("After pass by ref");
fred.Display();
Console.ReadLine();
//Person p = new Person();
}
static void Main(string[] args)
{
// Передача ссылочных типов по значению.
Console.WriteLine("***** Passing Person object by value *****");
Person fred = new Person("Fred", 12);
Console.WriteLine("\nBefore by value call, Person is:"); // перед вызовом
fred.Display();
SendAPersonByValue(fred);
Console.WriteLine("\nAfter by value call, Person is:"); // после вызова
fred.Display();
Console.WriteLine("***** Passing Person object by value 2 *****");
Person mel = new Person("Mel", 23);
Console.WriteLine("Before by ref call, Person is:"); // перед вызовом
mel.Display();
SendAPersonByReference(ref mel);
Console.WriteLine("After by ref call, Person is:"); // после вызова
mel.Display();
Console.ReadLine();
}
static void Main(string[] args)
{
// Passing ref-types by value.
Console.WriteLine("***** Passing Person object by value *****");
Person fred = new Person("Fred", 12);
Console.WriteLine("\nBefore by value call, Person is:");
fred.Display();
SendAPersonByValue(fred);
Console.WriteLine("\nAfter by value call, Person is:");
fred.Display();
Person mel = new Person("Mel", 23);
Console.WriteLine("Before by ref call, Person is:");
mel.Display();
SendAPersonByReference(ref mel);
Console.WriteLine("After by ref call, Person is:");
mel.Display();
Console.ReadLine();
}
static void Main(string[] args)
{
//Console.WriteLine("**** Refernce and value types in params ****");
//Console.WriteLine("=> Passing person by value");
//Person fred = new Person("Fred", 12);
//Console.WriteLine("Before by val call person is:");
//fred.Display();
//SendAPersonByValue(fred);
//Console.WriteLine("After by val call person is:");
//fred.Display();
Console.WriteLine("=> Using out parameter:");
int i;
SendUsingOut(out i); // Must be assigned in called method
Console.WriteLine("=> Using ref parameter:");
int j;
j = 1;
SendUsingRef(ref j); // int must be assigned befor using
Console.WriteLine("=> Passing person by ref");
Person nick = new Person("Nick", 76);
Console.WriteLine("Before by vref call person is:");
nick.Display();
SendAPersonByReference(ref nick); // nick must be assigned befor using
Console.WriteLine("After by ref call person is:");
nick.Display();
Console.WriteLine("=> Passing person with out parameter:");
Person jack;
SendAPersonByOut(out jack); // jack must be assigned in called method
jack.Display();
Console.ReadLine();
}
static void Main(string[] args)
{
Console.WriteLine("**** Passing Person Object By Value ****");
Person fred = new Person("Fred", 12);
Console.WriteLine("\nBefore by value call, Person is:");
fred.Display();
SemdAPersonByValue(fred);
Console.WriteLine("\nAfter call by value, Person is:");
fred.Display();
Console.WriteLine("**** Passing Person object By referece ****");
Person mel = new Person("Mel", 18);
Console.WriteLine("Before any call person is:");
mel.Display();
SendAPersonByReference(ref mel);
Console.WriteLine("After a call by ref the person is:");
mel.Display();
Console.ReadLine();
}
public static void Main(string[] args)
{
//Passing ref-types by Value
Console.WriteLine("*****Passing Person Object by value*****");
Person fred = new Person("Fred", 34);
Console.WriteLine("\n Before by value call, Person is");
fred.Display();
SendAPersonByValue(fred);
Console.WriteLine("\n After by value call, Person is");
fred.Display();
//Passing ref-types by ref
Console.WriteLine("****** Passing Person Object by Reference *****");
Person mel = new Person("Melvin", 23);
Console.WriteLine("Before by ref call, Person is");
mel.Display();
/** Returned the whole new Person Object ***/
SendAPersonByReference(ref mel);
Console.WriteLine("After by ref call, Person is");
mel.Display();
/* Changed only the value of age property of the Person Object*/
// Passing ref types by value
SendAPersonByValue(mel);
mel.Display();
// WORKING WITH DATABASEREADER CLASS
Console.WriteLine("*** Fun with Nullable Vlaue Types **** \n");
DatabaseReader dr = new DatabaseReader();
//If the value from GetIntFromDatabase is null
// assign local variable to 100
int myData = dr.GetIntFromDatabase() ?? 100;
Console.WriteLine("Value of myData: {0}", myData);
//Get int from 'database'
int?i = dr.GetIntFromDatabase();
if (i.HasValue)
{
Console.WriteLine("Value of i is {0}", i.Value);
}
else
{
Console.WriteLine(" Value of i is undefined");
}
//Get Bool from 'database'
bool?b = dr.GetBooleanFromDatabase();
if (b != null)
{
Console.WriteLine("Value of b is {0}", b.Value);
}
else
{
Console.WriteLine(" Value of b is undefined");
}
//Null Coealesicng Assignment Operation( c#8.0)
/* This operator assigns the left hand side to the righthand side only if the
* the left hand side is null
*/
int?nullableInt = null;
nullableInt ??= 24; // assigns nullableInt the value of 24 as is null
nullableInt ??= 14; // does not assign as nullableInt already has a value of 24
Console.WriteLine(nullableInt);
string? [] nullableString = { "ASD", "ASDF" };
TesterMethod(args: nullableString);
//Tuples => Getting starting with Tuples
(string, int, string)values = ("a", 2, "b");
// also follwing is valid
var values2 = ("x", 2, "z");
// Accessing tuple elements
Console.WriteLine($" First Item: {values.Item1}");
Console.WriteLine($" First Item: {values.Item2}");
Console.WriteLine($" First Item: {values.Item3}");
// Name values tuple
(string firstName, string lastName, int age)info = ("Hari", "Mahat", 34);
// can be accesed by ItemX= Item position, 1 in above is firstName
Console.WriteLine($" First Name: {info.Item1}");
// accing using name
Console.WriteLine($" First Item: {info.lastName}");
// values with Names
var info2 = (firstName : "Hari", lastName : "Mahat", age : 23);
// Calling Tuple as Methods Return values
var samples = FillTheseValues2();
Console.WriteLine($" Int is {samples.a}");
Console.WriteLine($" String is {samples.b}");
Console.WriteLine($" Boolean is {samples.c}");
// Destructed Tuple allows singple method call to get the individaul values of the
// structre by returning a tuple
Point p = new Point(-5, 6);
var pointValues = p.Deconstruct();
Console.WriteLine($" X is : {pointValues.xPos}");
Console.WriteLine($" Y is : {pointValues.yPos}");
// Using tuple value to get quadrant
Console.WriteLine(GetQuadtrant1(p));
}