public static UsingRefKeyWordWithClass ChangeA(UsingRefKeyWordWithClass a)
{
a.X = "The second value assigned to property: 2";
/*Note the next line creating new object and upon returning the *a* the value will be lost GARBAGE COLLECTED
* and the result will be that assigned at the line above*/
a = new UsingRefKeyWordWithClass {
X = "The 3rd value assigned to property: 3"
};
return(a);
}
#pragma warning disable
static void Main(string[] args)
{
Action <object> write = Console.WriteLine;
write("");
#region For C# classes and Struct
#if false
/*Instantiating a object*/
ClassesIntroduction person = new ClassesIntroduction();
/*Accessing the fields of a class */
person.FirstName = "Zahid";
person.LastName = "Farook";
write((person.FirstName, person.LastName));
ClassesIntroduction person1 = new ClassesIntroduction();
/*Accessing the fields of a class */
person1.FirstName = "John";
person1.LastName = "Doe";
write(person1.LastName);
write("");
/*Get the constant filed from cLASS*/
var personMode = ClassesIntroduction.LearningMode;
PersonPhone pNumber1 = new PersonPhone(12453, "Belgium");
write(PersonPhone.test(pNumber1));
write("");
PersonPhone2 pNumber2 = new PersonPhone2();
var country = pNumber2._country = "NL";
var pnum = pNumber2._phoneNumber = 123;
/*Get the constant filed from STRUCT*/
var lMode = PersonPhone2.LearningMode;
var res = PersonPhone2.CountryAndPhone(country, pnum, lMode);
/*Makes the static constructor execute */
ClassWithReadOnlyFields.getTheReadOnlyField();
/*This calls the constructor with one parameter*/
ClassWithReadOnlyFields classWithReadOnlyFields = new ClassWithReadOnlyFields(500);
/*printing the value of the assignment above*/
ClassWithReadOnlyFields.TheReadOnlyFieldDefinedTroughConstructor(classWithReadOnlyFields);
#endif
#endregion
#region For working with C Sharp class properties
#if false
Properties myP = new Properties();
myP.PlaneName = "PIA";
myP.TicketPrice = 120;
myP.PlaneName2 = "KLM";
myP.TicketPrice2 = 110;
/*print trough getter what is assigned*/
var res = myP.PlaneName;
var res2 = myP.PlaneName2;
var exBodiedP = new ExpressionBodiedProps();
exBodiedP.X = 4;
exBodiedP.Y = 4;
write(("Expression bodied props: ", exBodiedP.X, exBodiedP.Y));
var autoImProp = new AutoImplimentedProps();
autoImProp.Name = "Zahid";
autoImProp.LName = "Farook";
write(autoImProp.Name);
/*get the value of property initializer */
write(autoImProp.AuotPropInitializer);
PropertyAccessLevel x = new PropertyAccessLevel(12);
MakeReadOnlyOmitingTheSetter makeReadOnly = new MakeReadOnlyOmitingTheSetter("Good day");
write(makeReadOnly.J);
ExplicitReadOnlyPropTroughConstructor explicitReadOnlyProp = new ExplicitReadOnlyPropTroughConstructor(45);
//explicitReadOnlyProp.ID = 12; /*This will give an error since the prop is made read only*/
Person person = new Person("Zahid", "FARook");
// person.FirstName = ""; /*You can't do that since you are working with read only fields and they can only be assigned trough constructor*/
write(person.FullName);
#endif
#endregion
#region For C# Anonymous types
#if false
var john = new
{
Age = 68,
height = 4.5,
weight = 50
};
//john.Age = 65; /*Note here the value cannot be assigned since the anonymous types are read only */
write(john.Age);
//making an anonymous type using the props of an already existing object
AnonymousTypesAndMethods singer = new AnonymousTypesAndMethods();
var dName = "A";
singer.FName = dName;
var dancer = new
{
/*Note here the value cannot be assigned since the anonymous types are read only */
singer.FName,
singer.MName,
singer.LName,
};
write(dancer.FName);
var m1 = new WorkingWithMethod();
m1.MethodOne(m1);
m1.ExpressionBodiedMethod(m1, 10);
#endif
#endregion
#region For C# method overloading and invocation
#if false
MethodOverloding.MLoadingOne();
MethodOverloding.MLoadingTwo(1);
MethodOverloding.MLoadingThree(12, 23);
/*This will be assigned as the parameters are defined in the function so: l= 2 m12*/
MethodOverloding.MForNamedArgInvocation(2, 12);
/*This will be HOWEVER ALSO ASSIGNED AS THE PARAMETERS are defined in the function
* so regardless the order given here: m: 2, l: 12*/
MethodOverloding.MForNamedArgInvocation(m: 2, l: 12);
/*non-trailing named arguments are only allowed when the name and the position
* result in finding the same corresponding parameter.In other words if we omit the name of some parameters then
* the ORDER IN THE INVOCATION MUST MATCH WITH THAT OF ORIGINAL FOUND IN THE DEFINITION of the method */
MethodOverloding.MForNamedArgInvocation(l: 32, 113);
MethodOverloding.MWithOptionalParameter(2, 3);
MethodOverloding.MWithOptionalParameter(4);
/*The best time to use the NAMED ARGUMENT is when the optional are being passed*/
MethodOverloding.MWihtMultipleOptionalParams(w: 12, q: 8);
MethodOverloding.MUsingOptinalPatametersWithKeyWord(8, 9, 10, "TEst");
#endif
#endregion
#region For C# Constructors
#if false
var con = new ClassForConstructorPurpose(50);
write(con.Number);
ClassWithPrivateConstructor.Name("The initialization with private constructor");
var ConInitializer = new ClassForConstructerInitializer("Proton Persona");
var res = ConInitializer.TestConInitializer();
/*Remember!, static constructor does not have any access modifiers and It’s never called explicitly*/
write(ClassWithStaticConstructor.MyProperty);
#endif
#endregion
#region For C# Struct
#if false
var sc = new School("Hr", "Rotterdam");
sc.GetSchoolAndCity();
/*To avoid some performance issue we can use the REF keyword when passing an struct to an function*/
sc.GetSchoolAndCity(ref sc);
ReadOnlyStruct rds = new ReadOnlyStruct(true, true);
rds.CanWeUndoTheRain();
ExampleTypeRefStruct refStruct = new ExampleTypeRefStruct(12);
refStruct.TheBarkingDog();
write(refStruct.MyProperty);
sc = refStruct;/*this cannot be done since refStruct lives on stack and this assignment is on the heap*/
refStruct.ToString(); this cannot be done either
#endif
#endregion
#region For C# PASSING PARAMETERS BY VALUE AND BY REFERENCE
#if false
ValueType vType = new ValueType {
ThePropToBeNotChanged = 1
};
var res = vType.MethodWithValTypeRef(vType);
/*Check if the property got the value changed*/
if (vType.ThePropToBeNotChanged == res)
{
write("Yes, the prop was changed!");
}
else
{
write("No, the vType.ThePropToBeNotChanged wasn't changed");
}
/*Using the ref keyword within struct type*/
ValueType2 vType2 = new ValueType2 {
ThePropToBeNotChanged = 1
};
var res2 = vType2.MethodWithValTypeRef(ref vType2);
/*Check if the property got the value changed*/
if (vType2.ThePropToBeNotChanged == res2)
{
write("Yes, the prop was changed *even* it was a value type! You got thank to the REF KEWORD");
}
else
{
write("No, the vType.ThePropToBeNotChanged wasn't changed");
}
RefType refType = new RefType {
ThePropToBeNotChanged = 11
};
var res3 = refType.MethodWithValTypeRef(refType);
/*Check if the property got the value changed*/
if (refType.ThePropToBeNotChanged == res)
{
write("Yes, the refType.ThePropToBeNotChanged was changed!");
}
else
{
write("No, the ThePropToBeNotChanged wasn't changed");
}
/*Without ref keyword, when not careful the can be data loss. The garbage collection in this case*/
var refWithinClass = new UsingRefKeyWordWithClass {
X = "The initial value is: 1"
};
UsingRefKeyWordWithClass.ChangeA(refWithinClass);
write(refWithinClass.X);
/*Using REF keyword within class type TO AVOID the garbage collection in this case*/
var refWithinClass2 = new UsingRefKeyWordWithClass2 {
X = "The initial value is: 1"
};
UsingRefKeyWordWithClass2.ChangeA(ref refWithinClass2); /*Note the use of ref*/
write(refWithinClass2.X);
#endif
#endregion
#region For C# Out keyword
#if false
/*This will not do the work if the use will pass a string instead of int*/
//ClassForOutParameters.GetInputFromConsoleAndHandelNoException();
//ClassForOutParameters.GetInputAndHandelExceptionWithOut();
//var theUserInput = Console.ReadLine();
//ClassForOutParameters.OutKewWordAdvancedUse(theUserInput);
var ri = ClassForOutParameters.Divide(10, 3, out int kk);
Console.WriteLine(ri);
Console.WriteLine(kk);
#endif
#endregion
#region For C# in Parameter
#if false
var xForInParameter = new StructForInParameterTesting();
/*This is being allowed because we are not use the in keyword yet!*/
xForInParameter.MutableField = 12;
StructForInParameterTesting.TestMethodForInPara(xForInParameter);
var xForInParameter2 = new ClassForInParameterTesting();
xForInParameter2.MyProperty = 1;
ClassForInParameterTesting.TestMethodForInPara2(xForInParameter2);
#endif
#endregion
#region For C# null able types
#if false
int b = 3;
int?v = null;
int h = v.HasValue ? v.Value + b : b - 1;
int h1 = v ?? b - 1;/*using null coalescing*/
if (v != null)
{
write($"V was:{(v ?? v.Value)}");
}
else
{
write($"V was: NULL so the left side is evaluated: b - 1 ={b - 1} ");
}
string?l = null;
string j = (string)l ?? "";/*Null coalescing: If l != null than the value else the empty string*/
int x1 = 1;
int?x2 = null;
int?x3 = x2;
int x4 = x3 ?? 0;
int x5 = x3.HasValue ? x3.Value : -1;
#endif
#endregion
#region For C# Enum Type
#if false
KFCProduct chick = KFCProduct.chicken;
KFCProduct i = (KFCProduct)0; /*Cast a NUMBER to an ENUMERATION value. */
Console.WriteLine(i); /*The i will print the first named constants: chicken*/
int j = (int)chick; /*Cast a ENUMERATION to an NUMBER value*/
Console.WriteLine(j); /*The j will print the value of the first named constants: chicken*/
DaysOfWeek Di = (DaysOfWeek)3;
Console.WriteLine(Di);
KFCProduct enumMemberChicken;
if (Enum.TryParse <KFCProduct>("chicken", out enumMemberChicken))
{
Console.WriteLine($"successfully parse enumMemberChicken: {enumMemberChicken}");
}
/*Prints all the names of constants*/
foreach (string itmes in Enum.GetNames(typeof(KFCProduct)))
{
Console.WriteLine("\n" + itmes);
}
/*Prints all the value (indexes) of constants*/
foreach (int itmes in Enum.GetValues(typeof(KFCProduct)))
{
Console.WriteLine("\n" + itmes);
}
Console.WriteLine(
"All possible combinations of values with FlagsAttribute:");
for (int val = 0; val <= 16; val++)
{
Console.WriteLine("{0,5} - {1}", val, (SingleHue)val);
}
#if false
foreach (int val in Enum.GetValues(typeof(DaysOfWeek)))
{
Console.WriteLine(val + ": " + (DayOfWeek)val);
}
var myEnumMemberCount = Enum.GetNames(typeof(DaysOfWeek)).Length;
Console.WriteLine(myEnumMemberCount);
DaysOfWeek mondayAndWednesday = DaysOfWeek.Monday | DaysOfWeek.Wednesday;
Console.WriteLine(mondayAndWednesday);
DaysOfWeek meetingDays = DaysOfWeek.Monday & DaysOfWeek.Sunday;
Console.WriteLine(meetingDays);
DaysOfWeek workingFromHomeDays = DaysOfWeek.Monday | DaysOfWeek.Weekend;
Console.WriteLine(workingFromHomeDays);
Console.WriteLine($"Join a meeting by phone on {meetingDays & workingFromHomeDays}");
bool isMeetingOnTuesday = (meetingDays & DaysOfWeek.Sunday) == DaysOfWeek.Monday;
Console.WriteLine($"Is there a meeting on Tuesday: {isMeetingOnTuesday}");
#endif
#endif
#endregion
#region For C# Partial use within classes
#if false
ClassWithPartialKeyWord classWithPar = new ClassWithPartialKeyWord();
classWithPar.MethodOne();
classWithPar.MethodTwo();
ClassWithPartialFuncion.HelperForPartialMCall();
csharp.disp();
#endif
#endregion
#region For C# Extension methods
#if false
/*The following two lines are equals */
10.TheExtensionMethPowerOf();
ExtensionMethodsClass.TheExtensionMethPowerOf(10);
#endif
#endregion
#region For C# The object class's methods
#if true
var t = new ClassForConstructorPurpose(12);
Console.WriteLine(t.Number.ToString());
Console.WriteLine(t.GetHashCode());
var t1 = new ClassForConstructorPurpose(11);
Console.WriteLine(t.Equals(t));
Console.WriteLine(t.Equals(t1));
var cForFinalize = new ClassForFinalizer();
cForFinalize.ShowDuration();
Console.WriteLine(t.GetType());
// Create an instance of Person and assign values to its fields.
PersonForClone p1 = new PersonForClone();
p1.Age = 42;
p1.Name = "Sam";
p1.IdInfo = new IdInfo(6565);
// Perform a shallow copy of p1 and assign it to p2.
//PersonForClone p2 = p1.DeepCopy();
PersonForClone p2 = p1.ShallowCopy();
// Display values of p1, p2
Console.WriteLine("Original values of p1 and p2:");
Console.WriteLine("\n p1 instance values: ");
DisplayValues(p1);
Console.WriteLine("\n p2 instance values:");
DisplayValues(p2);