using System; using System.Data; class Class1{ static void Main(string[] args){ Console.WriteLine(ConvertDegreesToRadians (180)); Console.WriteLine(ConvertDegreesToRadians (90)); Console.WriteLine(ConvertDegreesToRadians (30)); } public static double ConvertDegreesToRadians (double degrees) { double radians = (Math.PI / 180) * degrees; return (radians); } }
Data Types
Nullable extension: Has Value And Equals
//http://arolibraries.codeplex.com/ //The MIT License (MIT) using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace AroLibraries.ExtensionMethods { public static class NullableExt { public static bool Ext_HasValueAndEquals<T>(this Nullable<T> source, T target) where T : struct { return source.HasValue && source.Value.Equals(target); } public static bool Ext_HasValueAndEquals<T>(this Nullable<T> source, Nullable<T> target) where T : struct { return source.HasValue && source.Value.Equals(target); } } }
Is it Nullable
//Microsoft Public License (Ms-PL) //http://visualizer.codeplex.com/license using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace Redwerb.BizArk.Core.TypeExt { /// <summary> /// Provides extension methods for Type. /// </summary> public static class TypeExt { public static bool IsNullable(this Type type) { if (type == null) return false; if (!type.IsGenericType) return false; if (type.GetGenericTypeDefinition() != typeof(Nullable<>)) return false; return true; } } }
Nulllable HasValue
using System; using System.Collections.Generic; using System.Text; public class MyTest { public static void NullableTest(Nullable<int> intVal1, int intVal2) { if (intVal1.HasValue == true) Console.WriteLine(intVal1); else Console.WriteLine("Value1 is NULL"); if (intVal2 > 0) Console.WriteLine(intVal2); else Console.WriteLine("Value2 is Null?"); } }
Nullable int Types
using System; using System.Collections.Generic; using System.Text; class DatabaseReader { // Nullable data field. public int? numbericValue; public bool? boolValue = true; // Note the nullable return type. public int? GetIntFromDatabase() { return numbericValue; } // Note the nullable return type. public bool? GetBoolFromDatabase() { return boolValue; } } class Program { static void Main(string[] args) { DatabaseReader dr = new DatabaseReader(); int? i = dr.GetIntFromDatabase(); if (i.HasValue) Console.WriteLine("Value of 'i' is: {0}", i); else Console.WriteLine("Value of 'i' is undefined."); // Get bool from 'database'. bool? b = dr.GetBoolFromDatabase(); if (b != null) Console.WriteLine("Value of 'b' is: {0}", b); else Console.WriteLine("Value of 'b' is undefined."); // If the value from GetIntFromDatabase() is null, // assign local variable to 100. int? myData = dr.GetIntFromDatabase() ?? 100; Console.WriteLine("Value of myData: {0}", myData); } }
Nullable bool Types
using System; using System.Collections.Generic; using System.Text; class DatabaseReader { // Nullable data field. public int? numbericValue; public bool? boolValue = true; // Note the nullable return type. public int? GetIntFromDatabase() { return numbericValue; } // Note the nullable return type. public bool? GetBoolFromDatabase() { return boolValue; } } class Program { static void Main(string[] args) { DatabaseReader dr = new DatabaseReader(); int? i = dr.GetIntFromDatabase(); if (i.HasValue) Console.WriteLine("Value of 'i' is: {0}", i); else Console.WriteLine("Value of 'i' is undefined."); // Get bool from 'database'. bool? b = dr.GetBoolFromDatabase(); if (b != null) Console.WriteLine("Value of 'b' is: {0}", b); else Console.WriteLine("Value of 'b' is undefined."); // If the value from GetIntFromDatabase() is null, // assign local variable to 100. int? myData = dr.GetIntFromDatabase() ?? 100; Console.WriteLine("Value of myData: {0}", myData); } }
Nullable variable
using System;
using System.Collections.Generic;
using System.Text;
public class Vector {
public double? R = null;
public double? Theta = null;
public double? ThetaRadians {
get {
return (Theta * Math.PI / 180.0);
}
}
public Vector(double? r, double? theta) {
if (r < 0) {
r = -r;
theta += 180;
}
theta = theta % 360;
R = r;
Theta = theta;
}
public static Vector operator +(Vector op1, Vector op2) {
try {
double newX = op1.R.Value * Math.Sin(op1.ThetaRadians.Value)
+ op2.R.Value * Math.Sin(op2.ThetaRadians.Value);
double newY = op1.R.Value * Math.Cos(op1.ThetaRadians.Value)
+ op2.R.Value * Math.Cos(op2.ThetaRadians.Value);
double newR = Math.Sqrt(newX * newX + newY * newY);
double newTheta = Math.Atan2(newX, newY) * 180.0 / Math.PI;
return new Vector(newR, newTheta);
} catch {
return new Vector(null, null);
}
}
public static Vector operator -(Vector op1) {
return new Vector(-op1.R, op1.Theta);
}
public static Vector operator -(Vector op1, Vector op2) {
return op1 + (-op2);
}
public override string ToString() {
string rString = R.HasValue ? R.ToString() : "null";
string thetaString = Theta.HasValue ? Theta.ToString() : "null";
return string.Format("({0}, {1})", rString, thetaString);
}
}
class Program {
public static void Main(string[] args) {
Vector v1 = GetVector("vector1");
Vector v2 = GetVector("vector1");
Console.WriteLine("{0} + {1} = {2}", v1, v2, v1 + v2);
Console.WriteLine("{0} - {1} = {2}", v1, v2, v1 - v2);
Console.ReadKey();
}
public static Vector GetVector(string name) {
Console.WriteLine("Input {0} magnitude:", name);
double? r = GetNullableDouble();
Console.WriteLine("Input {0} angle (in degrees):", name);
double? theta = GetNullableDouble();
return new Vector(r, theta);
}
public static double? GetNullableDouble() {
double? result;
string userInput = Console.ReadLine();
try {
result = double.Parse(userInput);
} catch {
result = null;
}
return result;
}
}
[/csharp]