Tech Talk – C# und das Microsoft .NET Framework Heinrich Wendel, DLR Simulations- und Softwaretechnik 30. Juli 2008

Architektur

Interoperabilität

C# - Namespaces // Defining namespaces namespace Dlr.Sistec { class Test { … } } // Nested namespaces namespace Dlr { namespace Sistec { class Test {…} } } // Using namespaces Dlr.Sistec.Test = new Dlr.Sistec.Test(); // Short form Using Dlr.Sistec; Test = new Test(); // Aliases Using ns = Dlr.Sistec; ns.Test = new ns.Test();

C# - Iterators Months months = new Months(); foreach (string temp in months) Console.WriteLine(temp); public class Months : IEnumerable { string[] month = { &quot;Januar&quot;, &quot;Februar&quot;, &quot;März&quot;, &quot;April&quot;, &quot;Mai&quot;, &quot;Juni&quot;, &quot;Juli&quot;, &quot;August&quot;, &quot;September&quot;, &quot;Oktober&quot;, &quot;November&quot;, &quot;Dezember&quot;}; public IEnumerator GetEnumerator() { for (int i = 0; i < month.Length; i++) yield return month[i]; } }

C# - Switch / Enums string s = Console.ReadLine();; switch(s) { case „ January “: … break; case „ Februar “: … break; case „ March “: … break; … }

C# - Switch / Enums [Flags] public enum Keys { Shift = 1, Ctrl = 2, Alt = 4 } Keys k = Keys.Shift | Keys.Ctrl if ((k & Keys.Shift) == Keys.Shift) {…}

C# - Properties public class Person { private string firstName ; private string lastName ; public void setFirstName (string name) this.firstName = name; } public string getLastName () return this.lastName; } public void setLastName (string name) this.lastName = name } public string getFirstName () return this.firstName; } } public class Person { public string FirstName { get { return firstName; } set { firstName = value ; } } private string firstName ; public string LastName { get { return lastName; } set { lastName = value ; } } private string lastName ; } Public class Person { public string FirstName { get; set ; } public string LastName { get; set ; } }

C# - Attributes [AttributeUsage(AttributeTargets.All)] public class DeveloperAttribute : Attribute { public string Zuname; public int PersID; public DeveloperAttribute(string name) { Zuname = name; } } [DeveloperAttribute(&quot;Meier&quot;, PersID = 8815)] class Program { static void Main(string[] args) { DeveloperAttribute attr = (DeveloperAttribute)Attribute. GetCustomAttribute(typeof(Program), typeof(DeveloperAttribute)); Console.WriteLine(&quot;Name: {0}&quot;, attr.Zuname ); Console.WriteLine(&quot;PersID: {0}&quot;, attr.PersID ); }

C# - Delegates / Events public class Logger { public delegate void Log(string message); private static Log log ger ; public static void Main(string[] args) { log ger = new Log(PrintToConsole); log ger.Invoke (&quot;message&quot;); } public static void PrintToConsole(string message) { Console.WriteLine(message); } } public class Logger { public delegate void Log(string message); private static Log logList; public static void Main(string[] args) { logList += new Log(PrintToConsole); logList += new Log(PrintTo File ); logList (&quot;message&quot;); } public static void PrintToConsole (string message) { … } public static void PrintTo File (string message) { … } } public class Logger { public delegate void Log(string message); public static event Log logList ; public static void Main(string[] args) { logList += PrintToConsole; logList += PrintTo File ; logList (&quot;message&quot;); } public static void PrintToConsole (string message) { … } public static void PrintTo File (string message) { … } }

C# - Lambda Funktionen public class Logger { public delegate void Log(string message); private static Log logList; public static void Main(string[] args) { logList = delegate(string message) { Console.WriteLine(message); }; logList(&quot;message&quot;); } } public class Logger { public delegate void Log(string message); private static Log logList; public static void Main(string[] args) { logList = message => { Console.WriteLine(message); }; logList(&quot;message&quot;); } } List <int> evenNumbers = list.FindAll( i => (i%2) == 0 );

C# - Constructors public class Point { public Point(int x, int y) { X = x; Y = y; } public Point() { } public int X { get; set; } public int Y { get; set; } } Point p = new Point(1, 2) Point p = new Point() P.X = 1; p.Y = 2; Point p = new Point { X = 1, Y = 2 }

C# - Constructors public class Point { public int X { get; set; } public int Y { get; set; } } public class Rectangle { public Point topLeft { get; set; } public Point bottomRight { get; set; } } Rectangle r = new Rectangle { topLeft = new Point{ X = 0, Y = 0 }, bottomRight = new Point { X = 2, Y = 2 } } Rectangle r = new Rectangle(); Point p1 = new Point(); p1.X = 0; p1.Y = 0; Point p2 = new Point(); p2.X = 2; p2.Y = 2; r.topLeft = p1; r.bottomRight = p2;

C# - Method Calls void FunctionA( ref int Val) { int x= Val; Val = x* 4; } int a= 5; FunctionA( ref a); Console.WriteLine(a); bool GetNodeValue( out int Val) { Val = 1; return true; } int Val; GetNodeValue(Val); Console.WriteLine(a); void Func(params int[] array) { Console.WriteLine(array.Length); } Func(1); Func(7,9); Func(new int[] {3,8,10});

C# - Extension Methods public static class ExtensionClass { public static int MultiplyByTwo( this int number) { return number * 2; } } public class Class1 { public static void Main(string[] args) { int number = 2; Console.WriteLine( number.MultiplyByTwo() ); } }

C# - Casting object [] myObjects = new object[1] myObjects[0] = new MyClass1(); string s; // Exception s = (string) myObjects[0] public static explicit operator String(MyClass1) { return “SomeString”; } If (myObjects[0] is string) { s = (string) myObjects[1] } s = myObjects[0] as string