Visual Basic supplies a number of predefined constants and enumerations for developers. Constants store values that remain constant throughout the execution of an application. Enumerations provide a convenient way to work with sets of related constants, and to associate constant values with names.
Conditional Compilation Constants
The following table lists the predefined constants available for conditional compilation.
||A string that corresponds to the current setting of the Active Solution Configuration box in the Configuration Manager.|
||A string representing the output type for the project or the setting of the command-line /target option. The possible values of
- "winexe" for a Windows application.
- "exe" for a console application.
- "library" for a class library.
- "module" for a module.
- The /target option may be set in the Visual Studio integrated development environment. For more information, see /target (Visual Basic).
||A number representing the Visual Basic version, in major.minor format. The version number for Visual Basic 2005 is 8.0.|
Print and Display Constants
When you call print and display functions, you can use the following constants in your code in place of the actual values.
||Carriage return/linefeed character combination.|
||Carriage return character.|
||Not the same as a zero-length string (""); used for calling external procedures.|
||Error number. User-defined error numbers should be greater than this value. For example:
||Not used in Microsoft Windows.|
||Not useful in Microsoft Windows.|
The following table lists and describes the enumerations provided by Visual Basic.
|AppWinStyle||Indicates the window style to use for the invoked program when calling the Shell function.|
|AudioPlayMode||Indicates how to play sounds when calling audio methods.|
|BuiltInRole||Indicates the type of role to check when calling the IsInRole method.|
|CallType||Indicates the type of procedure being invoked when calling the CallByName function.|
|CompareMethod||Indicates how to compare strings when calling comparison functions.|
|DateFormat||Indicates how to display dates when calling the FormatDateTime function.|
|DateInterval||Indicates how to determine and format date intervals when calling date-related functions.|
|DeleteDirectoryOption||Specifies what should be done when a directory that is to be deleted contains files or directories.|
|DueDate||Indicates when payments are due when calling financial methods.|
|FieldType||Indicates whether text fields are delimited or fixed-width.|
|FileAttribute||Indicates the file attributes to use when calling file-access functions.|
|FirstDayOfWeek||Indicates the first day of the week to use when calling date-related functions.|
|FirstWeekOfYear||Indicates the first week of the year to use when calling date-related functions.|
|MsgBoxResult||Indicates which button was pressed on a message box, returned by the MsgBox function.|
|MsgBoxStyle||Indicates which buttons to display when calling the MsgBox function.|
|OpenAccess||Indicates how to open a file when calling file-access functions.|
|OpenMode||Indicates how to open a file when calling file-access functions.|
|OpenShare||Indicates how to open a file when calling file-access functions.|
|RecycleOption||Specifies whether a file should be deleted permanently or placed in the Recycle Bin.|
|SearchOption||Specifies whether to search all or only top-level directories.|
|UICancelOption||Specifies what should be done if the user clicks Cancel during an operation.|
|UIOption||Specifies whether or not to show a progress dialog when copying, deleting, or moving files or directories.|
|VariantType||Indicates the type of a variant object, returned by the VarType function.|
|VbStrConv||Indicates which type of conversion to perform when calling the StrConv function.|