/*would this change the value of the above property? Yes since the struct is being * passed by reference *the keyword ref*/ public int MethodWithValTypeRef(ref ValueType2 valTypeRef) { var res = valTypeRef.ThePropToBeNotChanged = 33; Console.WriteLine("\n" + ThePropToBeNotChanged); return(res); }
#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);