Difference between revisions of "PChar"

From Free Pascal wiki
m (Fixed syntax highlighting; removed categories included in template)
m (Removed extra ))
 
Line 15: Line 15:
 
begin
 
begin
 
   s := 'Test';
 
   s := 'Test';
   Application.MessageBox( PChar(s)),'Title', MB_OK );
+
   Application.MessageBox( PChar(s),'Title', MB_OK );
 
end;  
 
end;  
 
</syntaxhighlight>
 
</syntaxhighlight>

Latest revision as of 21:51, 31 March 2020

Deutsch (de) English (en) español (es) français (fr) русский (ru)


Back to data types.


A PChar is Data type and a Pointer to a null-terminated string. The most important application of a PChar is interaction with system libraries like dll's.

Messagebox:

var 
  s: String;
begin
  s := 'Test';
  Application.MessageBox( PChar(s),'Title', MB_OK );
end;

Declaration:

var 
  p: PChar;

Valid assignments:

   p := 'This is a null-terminated string.';
   p := IntToStr(45);

Invalid assignments:

   p := 45;

The integer value is not casted to a PChar as might be expected.

See also