title: about delphi and dll
body: <pre><code>function：BOOL   IO_GetPageDimension(VOID   *p,   long   *imgwide,   long   *imghigh);
  
  Parameters
  p
  [in]   Pointer   to   structure   'set_attribute ';
  imgwide
  [out]   Syscan   scanner   return   accepting   the   scan   width;
  imghigh
  [out]   Syscan   scanner   return   accepting   the   scan   height;
  
  I defined the following code：
  type
  set_attribute = Record
    scan_mode:shortint;
    resolution:smallint;          
    brightness:shortint;          
    contrast:shortint;            
    gamma:shortint;               
    highlight:smallint;           
    shadow:smallint;              
    .......
  end;
  
  function IO_GetPageDimension(p: set_attribute; imgwide: Longint; imghigh:     Longint):Boolean;stdcall;external 'A8100.dll';
  call the following code in form
  begin
    p.highlight:= p.scan_mode:= 4;
    p.resolution:=300;        
    p.brightness:= 100;           
    p.contrast:= 80;          
    p.gamma:= 80;200;         
    p.shadow:= 200;           
    IO_GetPageDimension(p: set_attribute; imgwide: Longint; imghigh: Longint);
  end;
  </code></pre>
  
  <p>but a error at the line:IO_GetPageDimension(p: set_attribute; imgwide: Longint; imghigh: Longint);
  the error is:not enough actual parameters</p>
  
  <p>who can tell me the reason. i guess the function i defined has some problems</p>