Customizing Which Objects are Available in My (Visual Basic)
This topic describes how you can control which My objects are enabled by setting your project's _MYTYPE conditional-compilation constant. The Visual Studio Integrated Development Environment (IDE) keeps the _MYTYPE conditional-compilation constant for a project in sync with the project's type.
Predefined _MYTYPE Values
You must use the /define compiler option to set the _MYTYPE conditional-compilation constant. When specifying your own value for the _MYTYPE constant, you must enclose the string value in backslash/quotation mark (\") sequences. For example, you could use:
/define:_MYTYPE=\"WindowsForms\"
This table shows what the _MYTYPE conditional-compilation constant is set to for several project types.
| Project type | _MYTYPE value |
|---|---|
| Class Library | "Windows" |
| Console Application | "Console" |
| Web | "Web" |
| Web Control Library | "WebControl" |
| Windows Application | "WindowsForms" |
Windows Application, when starting with custom Sub Main |
"WindowsFormsWithCustomSubMain" |
| Windows Control Library | "Windows" |
| Windows Service | "Console" |
| Empty | "Empty" |
Note
All conditional-compilation string comparisons are case-sensitive, regardless of how the Option Compare statement is set.
Dependent _MY Compilation Constants
The _MYTYPE conditional-compilation constant, in turn, controls the values of several other _MY compilation constants:
| _MYTYPE | _MYAPPLICATIONTYPE | _MYCOMPUTERTYPE | _MYFORMS | _MYUSERTYPE | _MYWEBSERVICES |
|---|---|---|---|---|---|
| "Console" | "Console" | "Windows" | Undefined | "Windows" | TRUE |
| "Custom" | Undefined | Undefined | Undefined | Undefined | Undefined |
| "Empty" | Undefined | Undefined | Undefined | Undefined | Undefined |
| "Web" | Undefined | "Web" | FALSE | "Web" | FALSE |
| "WebControl" | Undefined | "Web" | FALSE | "Web" | TRUE |
| "Windows" or "" | "Windows" | "Windows" | Undefined | "Windows" | TRUE |
| "WindowsForms" | "WindowsForms" | "Windows" | TRUE | "Windows" | TRUE |
| "WindowsFormsWithCustomSubMain" | "Console" | "Windows" | TRUE | "Windows" | TRUE |
By default, undefined conditional-compilation constants resolve to FALSE. You can specify values for the undefined constants when compiling your project to override the default behavior.
Note
When _MYTYPE is set to "Custom", the project contains the My namespace, but it contains no objects. However, setting _MYTYPE to "Empty" prevents the compiler from adding the My namespace and its objects.
This table describes the effects of the predefined values of the _MY compilation constants.
| Constant | Meaning |
|---|---|
_MYAPPLICATIONTYPE |
Enables My.Application, if the constant is "Console," Windows," or "WindowsForms":- The "Console" version derives from ConsoleApplicationBase. and has fewer members than the "Windows" version. - The "Windows" version derives from ApplicationBase.and has fewer members than the "WindowsForms" version. - The "WindowsForms" version of My.Application derives from WindowsFormsApplicationBase. If the TARGET constant is defined to be "winexe", then the class includes a Sub Main method. |
_MYCOMPUTERTYPE |
Enables My.Computer, if the constant is "Web" or "Windows":- The "Web" version derives from ServerComputer, and has fewer members than the "Windows" version. - The "Windows" version of My.Computer derives from Computer. |
_MYFORMS |
Enables My.Forms, if the constant is TRUE. |
_MYUSERTYPE |
Enables My.User, if the constant is "Web" or "Windows":- The "Web" version of My.User is associated with the user identity of the current HTTP request.- The "Windows" version of My.User is associated with the thread's current principal. |
_MYWEBSERVICES |
Enables My.WebServices, if the constant is TRUE. |
_MYTYPE |
Enables My.Log, My.Request, and My.Response, if the constant is "Web". |
