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Operators[muuda]

Arithmetic and concatenation operators[muuda]

^ - Raises the first number power by another number[muuda]

* - Multiplies two numbers[muuda]

/ - Divides two numbers, and returns a floating point result[muuda]

\ - Divides two numbers, and returns an integer result[muuda]

% - Divides two numbers, and returns the remainder[muuda]

Mod - Divides two numbers, and returns the remainder[muuda]

+ - Adds two numbers[muuda]

+ - Concatenate two strings[muuda]

& - Concatenate two expressions as string[muuda]

- - Gives negative value to a number[muuda]

- - Between 2 numbers: gives negative value to a second number and adds two numbers[muuda]

Comparison Operators[muuda]

< - Less than comparison between 2 expressions[muuda]

  • true, if first expression is smaller than the second expression
  • false, if first expression is greater than or equal to the second expression

<= - Less than or equal to comparison between 2 expressions[muuda]

  • true, if first expression is smaller than or equal to the second expression
  • false, if first expression is greater than the second expression

> - Greater than comparison between 2 expressions[muuda]

  • true, if first expression is greater than the second expression
  • false, if first expression is smaller than or equal to the second expression

>= - Greater than or equal to comparison between 2 expressions[muuda]

  • true, if first expression is greater than or equal to the second expression
  • false, if first expression is smaller than the second expression

<> - inequality comparison between 2 expressions[muuda]

  • true, if first expression differs from the second expression
  • false, on all other cases

= - equality comparison between 2 expressions[muuda]

  • true, if first expression value is the same as the second expression value
  • false, on all other cases

Is - object reference comparison[muuda]

  • true, if the objects reference to the same object
  • false, on all other cases

IsNot - object reference comparison[muuda]

  • false, if the objects reference to the same object
  • true, on all other cases

TypeOf...Is - object variable comparison with a data type[muuda]

  • true, if thy are the same
  • false, on all other cases

Like - string comparison with pattern[muuda]

  • true, if pattern exist
  • false, on all other cases

Logical Operators[muuda]

NOT - (boolean)performs logical negation[muuda]

  • true, if condition is false
  • false, if condition is true

AND - (boolean)Performs a logical conjunction[muuda]

  • true, if both conditions are equal
  • false, on all other cases

ANDALSO - (boolean)short circuited AND[muuda]

  • true, if both conditions are equal
  • false, on all other cases

note : if the first expression is false, the other expression will never be evaluated

Or - (boolean)performs logical disjunction[muuda]

  • true, if at least of of the expressions is true
  • false, if both expressions are false

OrAlso - (boolean)short circuited OR[muuda]

  • true, if at least of of the expressions is true
  • false, if both expressions are false

note : if the first expression is true, the other expression will never be evaluated

Xor - (boolean)performs logical disjunction[muuda]

  • true, if expression differ
  • false, if expression are equal(both true or both false)

IsFalse; IsTrue - Determines expression boolean value[muuda]

note: you can not define only 1 of them, thy are a logical pair, and must be both declared if any

In addition[muuda]

  • if you use operators on numeric values rather then boolean, bitwise operation will be preformed
  • reminder:
    a imp b = (not a) or b
    a eqw b = not (a xor b)

Bit Shift Operators (pattern << amount)[muuda]

<< - Performs an arithmetic left shift, times amount, on a bit pattern[muuda]

>> - Performs an arithmetic right shift, times amount, on a bit pattern[muuda]

Other[muuda]

GetType - Returns a Type object[muuda]

AddressOf - Creates a procedure delegate instance that references the specific procedure[muuda]

How To[muuda]

String Manipulation[muuda]

How To create string consisting of the specified number of spaces?[muuda]

Dim specified_number as Byte = 4
Dim Test As String = Space(10)
Dim specified_number as Byte = 4
Dim Test As String = New String(" ", specified_number)

How To convert string to a number, type double?[muuda]

Dim Test_string As String = "123.456"
Dim Test_double As Double = Ctype(Val(Test_string), double)

How To determine the length of a number in characters?[muuda]

Dim Test As Integer = (123.456).ToString.Length

How To determine a possibly valid email?[muuda]

Public Shared Function IsEmail(ByVal Email As String) As Boolean
   Dim re As New Regex("^([a-zA-Z0-9_\-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$")
   If re.IsMatch(Email) Then Return True Else Return False
End Function