Name
Program Keyword
Syntax
programName
;Declarations
...Block
.
Description
The program
keyword begins an application. The
file extension for a program’s source file is
.dpr (for “Delphi
project”).
Tips and Tricks
Delphi accepts program parameters, for compatibility with standard Pascal, but it ignores them.
When the program starts, it first runs the initialization sections of all units, then it runs the program’s statement block. After the block ends, the program calls the
ExitProc
procedure, then runs the finalization section of each unit.Initialization sections run in the order of appearance in the program’s
uses
declaration, traversing each unit’suses
declaration. Finalization sections run in reverse order of the initialization sections. In other words, the first unit listed in the program’suses
declaration is the first unit to be initialized. Then, the first unit’s used units are initialized one at a time, each unit initializing its used units before its initialization code runs.The
Block
can be a simpleend
statement if the program has no code to run. In that case, immediately after every initialization section runs, the program ends by callingExitProc
and the finalization sections.
Example
program Echo;
// Echo command-line arguments, separated by spaces.
{$AppType Console}
var
I: Integer;
begin
if ParamCount > 0 then
Write(ParamStr(1));
for I := 2 to ParamCount do
Write(' ', ParamStr(I));
WriteLn;
end.
See Also
Asm Keyword, Begin Keyword, ExitProc Variable, Initialization ... |
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