Returns True if the alias exists, and false if it does not.

 

Property of

Session

Description

Method to determine if a database alias exists.

Syntax

<oRef>.isAlias(<cAliasName>,<nConfigMode> )

 

<caliasName>

The alias name you want to check.

<nConfigMode>

 optionally takes a second parameter specifying the configmode to use. defaults to checking with configmode of All (7)

  configMode options...

 

   1 = Virtual (for ODBC DSN)

   2 = Persistent (in BDE Config file)

   4 = Session (from a User BDE Alias or from an ODBC DSN)

   7 = Any of the above

 

Examples:

 

ODBC DSN ...............................................................

I have an ODBC DSN called 'accessbookstore'.

testing all options... returns true

?_app.session.isalias("accessbookstore")

?_app.session.isalias("accessbookstore",1)

?_app.session.isalias("accessbookstore",2)

?_app.session.isalias("accessbookstore",4)

?_app.session.isalias("accessbookstore",7)

 

PERSISTENT BDE ALIASES....................................................

Checking a persistent BDE Alias (for dBASE tables) ...

?_app.session.isalias("perm1")  //default

?_app.session.isalias("perm1",1)  //Virtual (for ODBC DSN)

?_app.session.isalias("perm1",2)  //Persistent (in BDE Config file)

?_app.session.isalias("perm1",4) //Session (from a User BDE Alias or from an ODBC DSN)

?_app.session.isalias("perm1",7) //Any of the above

returns ...

true       //default

false      //Virtual (for ODBC DSN)

true       //Persistent (in BDE Config file)

false      //Session (from a User BDE Alias or from an ODBC DSN)

true      //Any of the above

 

USER BDE ALIASES ..................................................................

using DBASESAMPLES user alias (defined in plus.ini)

?_app.session.isalias("dbasesamples")

?_app.session.isalias("dbasesamples",1)

?_app.session.isalias("dbasesamples",2)

?_app.session.isalias("dbasesamples",4)

?_app.session.isalias("dbasesamples",7)

true     //default

false    //Virtual (for ODBC DSN)

false    //Persistent (in BDE Config file)

true     //Session (from a User BDE Alias or from an ODBC DSN)

true     //Any of the above

 

TEMPORARY ALIASES............................................

_app.session.addalias("aTemp1","DBASE","C:\")

?_app.session.isalias("aTemp1")

?_app.session.isalias("aTemp1",1)

?_app.session.isalias("aTemp1",2)

?_app.session.isalias("aTemp1",4)

?_app.session.isalias("aTemp1",7)

 

_app.session.deletealias("aTemp1")

?" "

?_app.session.isalias("aTemp1")

?_app.session.isalias("aTemp1",1)

?_app.session.isalias("aTemp1",2)

?_app.session.isalias("aTemp1",4)

?_app.session.isalias("aTemp1",7)

returns ....

true    //default

false    //Virtual (for ODBC DSN)

false    //Persistent (in BDE Config file)

true     //Session (from a User BDE Alias or from an ODBC DSN)

true     //Any of the above

 

false    //default

false    //Virtual (for ODBC DSN)

false    //Persistent (in BDE Config file)

false     //Session (from a User BDE Alias or from an ODBC DSN)

false     //Any of the above