Name
Try Keyword
Syntax
tryStatements
... finallyStatements
... end; tryStatements
... exceptStatements
... end; tryStatements
... exceptHandlers
... end;
Description
The try
keyword introduces a
try
-except
statement or a
try
-finally
statement. The two
statements are related but serve different purposes.
The try
-finally
statement is
used to manage memory and other resources. It performs the statements
first in the try
part of the statement, then in
the finally
part of the statement. The statements
in the finally
part are executed no matter how
control leaves the try
part: exception, returning
from a subroutine with the Exit
procedure, or
exiting a loop with the Break
procedure.
The try
-except
statement
handles errors and exceptional conditions. It first performs the
statements in the try
part of the statement. If an
exception is raised, control transfers to the
except
part of the statement, where Delphi
searches for a matching exception handler. If the
except
part contains plain statements, Delphi
executes those statements, and then control continues after the end
of the try
-except
statement. If
the except
part contains one or more exception
handlers (which start with the on
directive),
Delphi searches for a matching handler. If it cannot find a matching
handler, control continues with the next
try
-except
statement in the
call stack.
Tips and Tricks
Use
try
-finally
to free temporary objects and other resources and to perform related cleanup activities. Typically, you should not need ...
Get Delphi in a Nutshell now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.