Pseudovariables

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Pseudovariables are terms used to display certain information in a variable window or the QuickWatch dialog box. You can enter a pseudovariable the same way you would enter a normal variable. Pseudovariables are not variables, however, and do not correspond to variable names in your program.

Example

Suppose you are writing a native code application and want to see the number of handles allocated in your application. In the Watch window, you can enter the following pseudovariable in the Name column, then press Return to evaluate it:

$handles

In native code, you can use the pseudovariables shown in this table:

Pseudovariable	Function
$handles	Displays the number of handles allocated in your application.
$vframe	Displays the address of the current stack frame.
$TID	Displays the thread ID for the current thread.
$ENV	Displays the size of the environment block. Trying to edit the size of the environment block (in the Value column) causes the contents of the environment block to be displayed in the Output window when you press Return. It does not change the size of the environment block.
$CMDLINE	Displays the size of the command line string that launched the program. Trying to edit the size (in the Value column) causes the command line string to be displayed in the Output window when you press Return. It does not change the size of the command line string.
$registername or @registername	Displays the contents of the register registername. Normally, you can display register contents just by entering the register name. The only time you need to use this syntax is when the register name overloads a variable name. If the register name is the same as a variable name in the current scope, the debugger interprets the name as a variable name. That's when $registername or @registername comes in handy.
$clk	Displays the time in clock cycles.
$user	Displays a structure with account information for the account running the application. For security reasons, the password information is not displayed.

In C# and Visual Basic, you can use the pseudovariables shown in this table:

Pseudovariable	Function
$exception	Displays information on the last exception. If no exception has occurred, evaluating $exception displays an error message. In Visual C# only, when the Exception Assistant is disabled, $exception is automatically added to the Locals window when an exception occurs.
$user	Displays a structure with account information for the account running the application. For security reasons, the password information is not displayed.

In Visual Basic, you can use the pseudovariables shown in the following table:

Pseudovariable	Function
$delete or $$delete	Deletes an implicit variable that was created in the Immediate window. The syntax is $delete, variable or $delete, variable.
$objectids or $listobjectids	Displays all active Object IDs as children of the specified expression. The syntax is $objectid, expression or $listobjectids, expression.
$N#	Displays object with Object ID equal to N.
$dynamic	Displays the special Dynamic View node for an object that implements the IDynamicMetaObjectProvider. Interface. The syntax is $dynamic, object. This feature applies only to code that uses .NET Framework version 4. See Dynamic View.

See Also

Tasks

How to: Watch an Expression in the Debugger

Other Resources

Variable Windows