Enhance standard SOLIDWORKS 3D bounding box by making its edges selectable
The following classifications list different standard types in Visual Basic grouped by categories. Each type allocates different size of memory storage. Some of the types have declaration character which can be used to explicitly define the type of the variable in a short form. Most of the types provide specific function to convert the value from a variant.
Numeric type variables are used to hold positive and negative integer values (without the decimal point), e.g. 1, 2, 10, -10, -1000 etc. Different numeric types allow storing different value ranges and requires different size of the allocated storage. The most commonly used type is Integer.
If the assigned value doesn’t fit the range Run-time error ‘6’ overflow will be displayed at the compile time.
Allocates 1 byte of storage. Value ranges from 0 through 255. The function of converting to Byte is CByte.
Allocates 2 bytes of storage. Value ranges from –32,768 through 32,767. The type declaration character for integer is %. The function of converting to Integer is CInt.
Allocates 4 bytes of storage. Value ranges from –2,147,483,648 through 2,147,486,647. The type declaration character for long is &. The function of converting to Long is CLng
Allocates 8 bytes of storage. Value ranges from -9,223,372,036,854,775,808 through 9,223,372,036,854,775,807. Type declaration character for LongLong is ^. LongLong is a valid declared type only on 64-bit platforms.
LongPtr usually used for writing portable code that can run in both 32-bit and 64-bit environments. In particular this is used in Windows 32 APIs for pointers and handles.
Numeric with decimal point
These types of variables are used to hold positive and negative numeric values with decimal points, i.e. 20.5, -152.89 etc. Different type of variables allow to store different value ranges with different precisions. The most commonly used type is Double. For high precision numbers either Currency or Decimal types can be used.
Allocates 4 bytes of storage. Value ranges from –3.402823E38 through –1.401298E–45 or 1.401298E–45 through 3.402823E38. The type declaration character for single is !. The function of converting to Single is CSng
Allocates 8 bytes of storage. Value ranges from –1.79769313486232E308 through –4.94065645841247E–324 or 1.79769313486232E308 through 4.94065645841247E–324. The type declaration character for double is #. The function of converting to Single is CDbl
Allocates 8 bytes of storage. Value ranges from –922,337,203,477.5808 through 922,337,203,685,477.5807. The type declaration character for integer is @. The function of converting to Currency is CCur
Allocates 14 bytes of storage. Value ranges from -79,228,162,514,264,337,593,543,950,335 through 79,228,162,514,264,337,593,543,950,335 or –7.2998162514264337593543950335 through 7.9228162514264337593543950335. The function of converting to Decimal is CDec. Note that variable of type Decimal must be declared as Variant and assigned using CDec function.
Logical variables are used in conditions and presented as 1 (True) or 0 (False)
Allocates 2 bytes of storage. Either True or False. The function of converting to Boolean is CBool
Text variables are holding literals and when defined are enclosed in double quotes “”.
Allocates 10 bytes plus the number of characters of storage. Value ranges from 0 through 2 billion characters. The function of converting to String is CStr
Date and Time
Variable holding the information about date and time.
Allocates 8 bytes of storage. Value ranges from January 1, 100 to December 31, 9999. The function of converting to String is CDate
These variables are any reference types which might hold complex data and structures.
Allocates 4 bytes of storage. Used in Late Binding
These variable types can hold any data object (either value type, reference type or arrays)
Allocates 16 bytes of storage. The function of converting to Variant is CVar
The code example below demonstrates declaration and conversion of various standard data types.
Sub main() Dim byteVar As Byte byteVar = 17 byteVar = CByte("12") 'converting from text value to byte byteVar = CByte(15.6) 'floating number is not acceptable so the value will be rounded to 16 Dim intVar As Integer intVar = 12567 intVar = CInt("124") Dim longVar As Long longVar = 1256936 longVar = CLng("-124") longVar = 123& Dim longLongVar As LongLong '64 bit only longLongVar = 103456 longLongVar = 7392984646^ Dim longPtrVar As LongPtr longPtrVar = 94874882 Dim singleVar As Single singleVar = 3.4E+38 '3.4 * 10^38 singleVar = CSng("15.656") singleVar = 12345.35! Dim doubleVar As Double doubleVar = 3.4E+100 doubleVar = CDbl("106.278856") 'holds more precise value with more floating digits doubleVar = 12345# 'force integer value to be converted to double Dim currVal As Currency currVal = 3105.6 currVal = CCur("31,256,78") currVal = 689.3458@ Dim decVal As Variant decVal = CDec(1E-18) Dim boolVar As Boolean boolVar = True boolVar = CBool(1) 'converted to true Dim strVar As String strVar = "Hello World" strVar = CStr(125) 'number converted to string Dim dateVar As Date dateVar = Now() 'assigns current date dateVar = CDate("10-Jun-2018") Dim objVar As Object Set objVar = Nothing Dim varVar As Variant varVar = Array("A", "B", "C") varVar = "Hello World" varVar = CVar(10.5) End Sub