Learning point

C# Booleans Very often, in programming, you will need a data type that can only have one of two values, like: YES / NO ON / OFF TRUE / FALSE For this, C# has a  bool  data type, which can take the values  true  or  false . Boolean Values A boolean type is declared with the  bool  keyword and can only take the values  true  or  false : Example bool isCSharpFun = true ; bool isFishTasty = false ; Console . WriteLine ( isCSharpFun ) ; // Outputs True Console . WriteLine ( isFishTasty ) ; // Outputs False However, it is more common to return boolean values from boolean expressions, for conditional testing (see below). Boolean Expression A  Boolean expression  is a C# expression that returns a Boolean value:  True  or  False . You can use a comparison operator, such as the  greater than  ( > ) operator to find out if an expression (or a variable) is true: E...

C# Strings Strings are used for storing text. A  string  variable contains a collection of characters surrounded by double quotes: Example Create a variable of type  string  and assign it a value: string greeting = "Hello" ; String Length A string in C# is actually an object, which contain properties and methods that can perform certain operations on strings. For example, the length of a string can be found with the  Length  property: Example string txt = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" ; Console . WriteLine ( "The length of the txt string is: " + txt . Length ) ; Other Methods There are many string methods available, for example  ToUpper()  and  ToLower() , which returns a copy of the string converted to uppercase or lowercase: Example string txt = "Hello World" ; Console . WriteLine ( txt . ToUpper ( ) ) ; // Outputs "HELLO WORLD" Console . WriteLine ( txt . ToLower ( ) ) ; // Output...