我有一个在delphi 6中运行良好的delphi项目，但是当我升级到XE时它不起作用。 我知道它与delphi XE中的新unicode类型有关，我已经尝试将参数的定义从pchar更改为pansichar，ansichar但到目前为止还没有成功。谁能看到我做错了什么？ 我的项目调用第三方dll中的函数，其定义如下：
type
PPChar = array of PChar;
{$EXTERNALSYM gsapi_init_with_args}
function gsapi_init_with_args(pinstance:Pgs_main_instance;argc:integer;argv:PPChar):integer; stdcall;
Implementation
{$EXTERNALSYM gsapi_init_with_args}
function gsapi_init_with_args; stdcall; external gsdll32 name 'gsapi_init_with_args';
以下是我如何调用该函数。
procedure PSPDF(input : string; output:string);
var
code:integer;
instance:Pointer;
argv:array of PAnsiChar;
begin
new(instance);
setlength(argv,10);
code:=gsapi_new_instance(@instance,nil);
if code<>0 then
begin
raise Exception.Create('Impossible to open an instance of ghostscript. Error code: '+IntToStr(code));
end;
try
argv[0] := PAnsiChar('ps2pdf');
argv[1] := PAnsiChar('-dNOPAUSE');
argv[2] := PAnsiChar('-dBATCH');
argv[3] := PAnsiChar('-dSAFER');
argv[4] := PAnsiChar('-sDEVICE=pdfwrite');
argv[5] := PAnsiChar(PAnsiString('-sOutputFile='+output));
argv[6] := PAnsiChar('-c');
argv[7] := PAnsiChar('.setpdfwrite');
argv[8] := PAnsiChar('-f');
argv[9] := PAnsiChar(PAnsiString(input));
gsapi_new_instance(instance, nil);
code := gsapi_init_with_args(instance,length(argv),@argv[0]);
if code<0 then
raise Exception.Create('ERROR: init_args: '+IntToStr(code));
gsapi_exit(instance);
gsapi_delete_instance(instance);
finally
end;
end;
如果有人可以帮助我，我将非常感激。
马里奥。
答案 0 :(得分：4)
将PChar更改为PAnsiChar是正确的做法，但是array of ...在DLL函数参数中使用是不安全的，即使在Delphi 6项目中使用也是错误的。查看official Ghostscript documentation后，请在两个项目中尝试：
interface
type
PPAnsiChar = ^PAnsiChar;
{$NODEFINE PPAnsiChar}
function gsapi_new_instance(var pinstance: Pointer; caller_handle: Pointer): Integer; stdcall;
{$EXTERNALSYM gsapi_new_instance}
procedure gsapi_delete_instance(instance: Pointer); stdcall;
{$EXTERNALSYM gsapi_delete_instance}
function gsapi_init_with_args(instance: Pointer; argc: Integer; argv: PPAnsiChar): Integer; stdcall;
{$EXTERNALSYM gsapi_init_with_args}
function gsapi_exit(instance: Pointer): Integer; stdcall;
{$EXTERNALSYM gsapi_exit}
implementation
function gsapi_new_instance; external gsdll32 name 'gsapi_new_instance';
procedure gsapi_delete_instance; external gsdll32 name 'gsapi_delete_instance';
function gsapi_init_with_args; external gsdll32 name 'gsapi_init_with_args';
function gsapi_exit; external gsdll32 name 'gsapi_exit';
procedure PSPDF(input : AnsiString; output: AnsiString);
var
code:integer;
instance: Pointer;
argv: array of PAnsiChar;
begin
code := gsapi_new_instance(instance, nil);
if code < 0 then
raise Exception.Create('Impossible to open an instance of ghostscript. Error code: '+IntToStr(code));
try
SetLength(argv, 10);
argv[0] := PAnsiChar('ps2pdf');
argv[1] := PAnsiChar('-dNOPAUSE');
argv[2] := PAnsiChar('-dBATCH');
argv[3] := PAnsiChar('-dSAFER');
argv[4] := PAnsiChar('-sDEVICE=pdfwrite');
argv[5] := PAnsiChar('-sOutputFile='+output);
argv[6] := PAnsiChar('-c');
argv[7] := PAnsiChar('.setpdfwrite');
argv[8] := PAnsiChar('-f');
argv[9] := PAnsiChar(input);
code := gsapi_init_with_args(instance, Length(argv), @argv[0]);
if code < 0 then
raise Exception.Create('ERROR: init_args: '+IntToStr(code));
try
...
finally
gsapi_exit(instance);
end;
finally
gsapi_delete_instance(instance);
end;
end;
更新：这是gsapi.pas unit的更正版本，应该在两个Delphi版本中都有效：
// Copyright (c) 2001-2002 Alessandro Briosi
//
// Permission is hereby granted, free of charge, to any person
// obtaining a copy of this software and associated documentation
// files (the "Software"), to deal in the Software without
// restriction, including without limitation the rights to use, copy,
// modify, merge, publish, distribute, sublicense, and/or sell copies
// of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
// BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
// ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
// CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
//
//
// This software was written by Alessandro Briosi with the
// assistance of Russell Lang, as an example of how the
// Ghostscript DLL may be used Delphi.
//
unit gsapi;
interface
uses
Windows;
// {$HPPEMIT '#include <iminst.h>'}
const
gsdll32 = 'gsdll32.dll';
STDIN_BUF_SIZE = 128;
{$EXTERNALSYM STDIN_BUF_SIZE}
STDOUT_BUF_SIZE = 128;
{$EXTERNALSYM STDOUT_BUF_SIZE}
STDERR_BUF_SIZE = 128;
{$EXTERNALSYM STDERR_BUF_SIZE}
DISPLAY_VERSION_MAJOR = 1;
{$EXTERNALSYM DISPLAY_VERSION_MAJOR}
DISPLAY_VERSION_MINOR = 0;
{$EXTERNALSYM DISPLAY_VERSION_MINOR}
//* Define the color space alternatives */
DISPLAY_COLORS_NATIVE = $01;
{$EXTERNALSYM DISPLAY_COLORS_NATIVE}
DISPLAY_COLORS_GRAY = $02;
{$EXTERNALSYM DISPLAY_COLORS_GRAY}
DISPLAY_COLORS_RGB = $04;
{$EXTERNALSYM DISPLAY_COLORS_RGB}
DISPLAY_COLORS_CMYK = $08;
{$EXTERNALSYM DISPLAY_COLORS_CMYK}
DISPLAY_COLORS_MASK = $000f;
{$EXTERNALSYM DISPLAY_COLORS_MASK}
//* Define whether alpha information, or an extra unused bytes is included */
//* DISPLAY_ALPHA_FIRST and DISPLAY_ALPHA_LAST are not implemented */
DISPLAY_ALPHA_NONE = $00;
{$EXTERNALSYM DISPLAY_ALPHA_NONE}
DISPLAY_ALPHA_FIRST = $10;
{$EXTERNALSYM DISPLAY_ALPHA_FIRST}
DISPLAY_ALPHA_LAST = $20;
{$EXTERNALSYM DISPLAY_ALPHA_LAST}
DISPLAY_UNUSED_FIRST = $40; //* e.g. Mac xRGB */
{$EXTERNALSYM DISPLAY_UNUSED_FIRST}
DISPLAY_UNUSED_LAST = $80; //* e.g. Windows BGRx */
{$EXTERNALSYM DISPLAY_UNUSED_LAST}
DISPLAY_ALPHA_MASK = $0070;
{$EXTERNALSYM DISPLAY_ALPHA_MASK}
// * Define the depth per component for DISPLAY_COLORS_GRAY,
// * DISPLAY_COLORS_RGB and DISPLAY_COLORS_CMYK,
// * or the depth per pixel for DISPLAY_COLORS_NATIVE
// * DISPLAY_DEPTH_2 and DISPLAY_DEPTH_12 have not been tested.
// *
DISPLAY_DEPTH_1 = $0100;
{$EXTERNALSYM DISPLAY_DEPTH_1}
DISPLAY_DEPTH_2 = $0200;
{$EXTERNALSYM DISPLAY_DEPTH_2}
DISPLAY_DEPTH_4 = $0400;
{$EXTERNALSYM DISPLAY_DEPTH_4}
DISPLAY_DEPTH_8 = $0800;
{$EXTERNALSYM DISPLAY_DEPTH_8}
DISPLAY_DEPTH_12 = $1000;
{$EXTERNALSYM DISPLAY_DEPTH_12}
DISPLAY_DEPTH_16 = $2000;
{$EXTERNALSYM DISPLAY_DEPTH_16}
//* unused (1<<14) */
//* unused (1<<15) */
DISPLAY_DEPTH_MASK = $ff00;
{$EXTERNALSYM DISPLAY_DEPTH_MASK}
// * Define whether Red/Cyan should come first,
// * or whether Blue/Black should come first
// */
DISPLAY_BIGENDIAN = $00000; //* Red/Cyan first */
{$EXTERNALSYM DISPLAY_BIGENDIAN}
DISPLAY_LITTLEENDIAN = $10000; //* Blue/Black first */
{$EXTERNALSYM DISPLAY_LITTLEENDIAN}
DISPLAY_ENDIAN_MASK = $00010000;
{$EXTERNALSYM DISPLAY_ENDIAN_MASK}
//* Define whether the raster starts at the top or bottom of the bitmap */
DISPLAY_TOPFIRST = $00000; //* Unix, Mac */
{$EXTERNALSYM DISPLAY_TOPFIRST}
DISPLAY_BOTTOMFIRST = $20000; //* Windows */
{$EXTERNALSYM DISPLAY_BOTTOMFIRST}
DISPLAY_FIRSTROW_MASK = $00020000;
{$EXTERNALSYM DISPLAY_FIRSTROW_MASK}
//* Define whether packing RGB in 16-bits should use 555
// * or 565 (extra bit for green)
// */
DISPLAY_NATIVE_555 = $00000;
{$EXTERNALSYM DISPLAY_NATIVE_555}
DISPLAY_NATIVE_565 = $40000;
{$EXTERNALSYM DISPLAY_NATIVE_565}
DISPLAY_555_MASK = $00040000;
{$EXTERNALSYM DISPLAY_555_MASK}
type
TGSAPIrevision = record
product: PAnsiChar;
copyright: PAnsiChar;
revision: Longint;
revisiondat: Longint;
end;
TStdioFunction = function(caller_handle: Pointer; buf: PAnsiChar; len: Integer): Integer; stdcall;
TPollFunction = function(caller_handle: Pointer): Integer; stdcall;
TDisplayEvent = function(handle: Pointer; device: Pointer): Integer; cdecl;
TDisplayPreResizeEvent = function(handle: Pointer; device: Pointer;
width: Integer; height: Integer; raster: Integer; format: UINT): Integer; cdecl;
TDisplayResizeEvent = function(handle: Pointer; device: Pointer;
width: Integer; height: Integer; raster: Integer; format: UINT; pimage: PAnsiChar): Integer; cdecl;
TDisplayPageEvent = function(handle: Pointer; device: Pointer; copies: Integer; flush: Integer): Integer; cdecl;
TDisplayUpdateEvent = function(handle: Pointer; device: Pointer; x: Integer; y: Integer; w: Integer; h: Integer): Integer; cdecl;
TDisplayMemAlloc = procedure(handle: Pointer; device: Pointer; size: ulong); cdecl;
TDisplayMemFree = function(handle: Pointer; device: Pointer; mem: Pointer): Integer; cdecl;
TDisplayCallback = record
size: Integer;
version_major: Integer;
version_minor: Integer;
// New device has been opened */
// This is the first event from this device. */
display_open: TDisplayEvent;
// Device is about to be closed. */
// Device will not be closed until this function returns. */
display_preclose: TDisplayEvent;
// Device has been closed. */
// This is the last event from this device. */
display_close: TDisplayEvent;
// Device is about to be resized. */
// Resize will only occur if this function returns 0. */
// raster is byte count of a row. */
display_presize: TDisplayPreResizeEvent;
// Device has been resized. */
// New pointer to raster returned in pimage */
display_size: TDisplayResizeEvent;
// flushpage */
display_sync: TDisplayEvent;
// showpage */
// If you want to pause on showpage, then don't return immediately */
display_page: TDisplayPageEvent;
// Notify the caller whenever a portion of the raster is updated. */
// This can be used for cooperative multitasking or for
// progressive update of the display.
// This function pointer may be set to NULL if not required.
//
display_update: TDisplayUpdateEvent;
// Allocate memory for bitmap */
// This is provided in case you need to create memory in a special
// way, e.g. shared. If this is NULL, the Ghostscript memory device
// allocates the bitmap. This will only called to allocate the
// image buffer. The first row will be placed at the address
// returned by display_memalloc.
//
display_memalloc: TDisplayMemAlloc;
// Free memory for bitmap */
// If this is NULL, the Ghostscript memory device will free the bitmap */
display_memfree: TDisplayMemFree;
end;
PPAnsiChar = ^PAnsiChar;
{$NODEFINE PPAnsiChar}
function gsapi_revision(var pr: TGSAPIrevision; len: Integer): Integer; stdcall;
{$EXTERNALSYM gsapi_revision}
function gsapi_new_instance(var pinstance: Pointer; caller_handle: Pointer): Integer; stdcall;
{$EXTERNALSYM gsapi_new_instance}
procedure gsapi_delete_instance(pinstance: Pointer); stdcall;
{$EXTERNALSYM gsapi_delete_instance}
function gsapi_set_stdio(pinstance: Pointer;
stdin_fn: TStdioFunction; stdout_fn: TStdioFunction;
stderr_fn: TStdioFunction): Integer; stdcall;
{$EXTERNALSYM gsapi_set_stdio}
function gsapi_set_poll(pinstance: Pointer; poll_fn: TPollFunction): Integer; stdcall;
{$EXTERNALSYM gsapi_set_poll}
function gsapi_set_display_callback(pinstance: Pointer; const callback: TDisplayCallback): Integer; stdcall;
{$EXTERNALSYM gsapi_set_display_callback}
function gsapi_init_with_args(pinstance: Pointer; argc: Integer; argv: PPAnsiChar): Integer; stdcall;
{$EXTERNALSYM gsapi_init_with_args}
function gsapi_run_string_begin(pinstance: Pointer; user_errors: Integer; var pexit_code: Integer): Integer; stdcall;
{$EXTERNALSYM gsapi_run_string_begin}
function gsapi_run_string_continue(pinstance: Pointer; str: PAnsiChar; len: Integer; user_errors: Integer; var pexit_code: Integer): Integer; stdcall;
{$EXTERNALSYM gsapi_run_string_continue}
function gsapi_run_string_end(pinstance: Pointer; user_errors: Integer; var pexit_code: Integer): Integer; stdcall;
{$EXTERNALSYM gsapi_run_string_end}
function gsapi_run_string_with_length(pinstance: Pointer; str: PAnsiChar; len: Integer; user_errors: Integer; var pexit_code: Integer): Integer; stdcall;
{$EXTERNALSYM gsapi_run_string_with_length}
function gsapi_run_string(pinstance: Pointer; str: PAnsiChar; user_errors: Integer; var pexit_code: Integer): Integer; stdcall;
{$EXTERNALSYM gsapi_run_string}
function gsapi_run_file(pinstance: Pointer; file_name: PAnsiChar; user_errors: Integer; var pexit_code: Integer): Integer; stdcall;
{$EXTERNALSYM gsapi_run_file}
function gsapi_exit(pinstance: Pointer): Integer; stdcall;
{$EXTERNALSYM gsapi_exit}
implementation
function gsapi_revision; external gsdll32 name 'gsapi_revision';
function gsapi_new_instance; external gsdll32 name 'gsapi_new_instance';
procedure gsapi_delete_instance; external gsdll32 name 'gsapi_delete_instance';
function gsapi_set_stdio; external gsdll32 name 'gsapi_set_stdio';
function gsapi_set_poll; external gsdll32 name 'gsapi_set_poll';
function gsapi_set_display_callback; external gsdll32 name 'gsapi_set_display_callback';
function gsapi_init_with_args; external gsdll32 name 'gsapi_init_with_args';
function gsapi_run_string_begin; external gsdll32 name 'gsapi_run_string_begin';
function gsapi_run_string_continue; external gsdll32 name 'gsapi_run_string_continue';
function gsapi_run_string_end; external gsdll32 name 'gsapi_run_string_end';
function gsapi_run_string_with_length; external gsdll32 name 'gsapi_run_string_with_length';
function gsapi_run_string; external gsdll32 name 'gsapi_run_string';
function gsapi_run_file; external gsdll32 name 'gsapi_run_file';
function gsapi_exit; external gsdll32 name 'gsapi_exit';
end.
答案 1 :(得分：0)
旧的Delphi 6 PChar是Unicode Delphi（2009+）上的PAnsiChar，所以如果你将所有PChar引用改为PAnsiChar，一切都应该有效。
（包括你的Pgs_main_instance声明，如果有任何PChar在那里）
type
PPAnsiChar = array of PAnsiChar;
{$EXTERNALSYM gsapi_init_with_args}
function gsapi_init_with_args(pinstance: Pgs_main_instance;
argc: Integer; argv:PPAnsiChar): Integer; stdcall;
implementation
function gsapi_init_with_args(pinstance: Pgs_main_instance;
argc: Integer; argv:PPAnsiChar): Integer;
external gsdll32 name 'gsapi_init_with_args';
致电代码：
var
argv:PPAnsiChar;
instance: Pointer;
begin
new(instance); //how many bytes, this really doesn't make sense with a untyped pointer!
setlength(argv, 4);
argv[0] := PAnsiChar('ps2pdf');
argv[1] := PAnsiChar('-dNOPAUSE');
argv[2] := PAnsiChar('-dBATCH');
argv[3] := PAnsiChar('-dSAFER');
gsapi_init_with_args(instance, Length(argv), argv);
end;
要了解Unicode中的 new ，我建议您阅读MarcoCantù撰写的Delphi and Unicode白皮书。