我遇到的链接错误有问题：
错误 112 错误 LNK2019：未解析的外部符号 HPDF_Stream_WriteToStreamWithDeflate 在函数 HPDF_Stream_WriteToStream C:\Users\tykab\OneDrive\Dokumenty\Visual Studio 2013\Projects\PDF2\PDF2\hpdf_streams.obj PDF2 中引用
错误 111 错误 LNK2019：函数 LoadPngImageFromStream C:\Users\tykab\OneDrive\Dokumenty\Visual Studio 2013\Projects\PDF2\PDF2\hpdf_doc_png.obj 中引用的未解析外部符号 HPDF_Image_LoadPngImage
错误 113 error LNK1120: 2 unresolved externals C:\Users\tykab\OneDrive\Dokumenty\Visual Studio 2013\Projects\PDF2\Toradex_CE800\Debug\PDF2.exe PDF2
我在这个项目中使用 Visual Studio 2013。源代码是用 C 编程语言编写的，我使用与错误相关的 Hpdf_stream.h 的 C++ 头文件具有外部“C”标识符。我把这个标题的代码放在下面：
#ifndef _HPDF_STREAMS_H
#define _HPDF_STREAMS_H
#include "hpdf_list.h"
#include "hpdf_encrypt.h"
#ifdef __cplusplus
extern "C" {
#endif
#define HPDF_STREAM_SIG_BYTES 0x5354524DL
typedef enum _HPDF_StreamType {
HPDF_STREAM_UNKNOWN = 0,
HPDF_STREAM_CALLBACK,
HPDF_STREAM_FILE,
HPDF_STREAM_MEMORY
} HPDF_StreamType;
#define HPDF_STREAM_FILTER_NONE 0x0000
#define HPDF_STREAM_FILTER_ASCIIHEX 0x0100
#define HPDF_STREAM_FILTER_ASCII85 0x0200
#define HPDF_STREAM_FILTER_FLATE_DECODE 0x0400
#define HPDF_STREAM_FILTER_DCT_DECODE 0x0800
#define HPDF_STREAM_FILTER_CCITT_DECODE 0x1000
typedef enum _HPDF_WhenceMode {
HPDF_SEEK_SET = 0,
HPDF_SEEK_CUR,
HPDF_SEEK_END
} HPDF_WhenceMode;
typedef struct _HPDF_Stream_Rec *HPDF_Stream;
typedef HPDF_STATUS
(*HPDF_Stream_Write_Func) (HPDF_Stream stream,
const HPDF_BYTE *ptr,
HPDF_UINT siz);
typedef HPDF_STATUS
(*HPDF_Stream_Read_Func) (HPDF_Stream stream,
HPDF_BYTE *ptr,
HPDF_UINT *siz);
typedef HPDF_STATUS
(*HPDF_Stream_Seek_Func) (HPDF_Stream stream,
HPDF_INT pos,
HPDF_WhenceMode mode);
typedef HPDF_INT32
(*HPDF_Stream_Tell_Func) (HPDF_Stream stream);
typedef void
(*HPDF_Stream_Free_Func) (HPDF_Stream stream);
typedef HPDF_UINT32
(*HPDF_Stream_Size_Func) (HPDF_Stream stream);
typedef struct _HPDF_MemStreamAttr_Rec *HPDF_MemStreamAttr;
typedef struct _HPDF_MemStreamAttr_Rec {
HPDF_List buf;
HPDF_UINT buf_siz;
HPDF_UINT w_pos;
HPDF_BYTE *w_ptr;
HPDF_UINT r_ptr_idx;
HPDF_UINT r_pos;
HPDF_BYTE *r_ptr;
} HPDF_MemStreamAttr_Rec;
typedef struct _HPDF_Stream_Rec {
HPDF_UINT32 sig_bytes;
HPDF_StreamType type;
HPDF_MMgr mmgr;
HPDF_Error error;
HPDF_UINT size;
HPDF_Stream_Write_Func write_fn;
HPDF_Stream_Read_Func read_fn;
HPDF_Stream_Seek_Func seek_fn;
HPDF_Stream_Free_Func free_fn;
HPDF_Stream_Tell_Func tell_fn;
HPDF_Stream_Size_Func size_fn;
void* attr;
} HPDF_Stream_Rec;
int
main(int argc, char **argv);
__declspec(dllimport) HPDF_Stream
HPDF_MemStream_New (HPDF_MMgr mmgr,
HPDF_UINT buf_siz);
__declspec(dllimport) HPDF_BYTE*
HPDF_MemStream_GetBufPtr (HPDF_Stream stream,
HPDF_UINT index,
HPDF_UINT *length);
HPDF_UINT __cdecl
HPDF_MemStream_GetBufSize(HPDF_Stream stream);
HPDF_UINT __cdecl
HPDF_MemStream_GetBufCount (HPDF_Stream stream);
__declspec(dllimport) HPDF_STATUS
HPDF_MemStream_Rewrite (HPDF_Stream stream,
HPDF_BYTE *buf,
HPDF_UINT size);
__declspec(dllimport) void
HPDF_MemStream_FreeData (HPDF_Stream stream);
HPDF_STATUS __cdecl
HPDF_Stream_WriteToStream (HPDF_Stream src,
HPDF_Stream dst,
HPDF_UINT filter,
HPDF_Encrypt e);
__declspec(dllimport) HPDF_Stream
HPDF_FileReader_New (HPDF_MMgr mmgr,
const char *fname);
__declspec(dllimport) HPDF_Stream
HPDF_FileWriter_New (HPDF_MMgr mmgr,
const char *fname);
__declspec(dllimport) HPDF_Stream
HPDF_CallbackReader_New (HPDF_MMgr mmgr,
HPDF_Stream_Read_Func read_fn,
HPDF_Stream_Seek_Func seek_fn,
HPDF_Stream_Tell_Func tell_fn,
HPDF_Stream_Size_Func size_fn,
void* data);
__declspec(dllimport) HPDF_Stream
HPDF_CallbackWriter_New (HPDF_MMgr mmgr,
HPDF_Stream_Write_Func write_fn,
void* data);
__declspec(dllimport) void
HPDF_Stream_Free (HPDF_Stream stream);
__declspec(dllimport) HPDF_STATUS
HPDF_Stream_WriteChar (HPDF_Stream stream,
char value);
__declspec(dllimport) HPDF_STATUS
HPDF_Stream_WriteStr (HPDF_Stream stream,
const char *value);
HPDF_STATUS
HPDF_Stream_WriteUChar (HPDF_Stream stream,
HPDF_BYTE value);
__declspec(dllimport) HPDF_STATUS
HPDF_Stream_WriteInt (HPDF_Stream stream,
HPDF_INT value);
__declspec(dllimport) HPDF_STATUS
HPDF_Stream_WriteUInt (HPDF_Stream stream,
HPDF_UINT value);
__declspec(dllimport) HPDF_STATUS
HPDF_Stream_WriteReal (HPDF_Stream stream,
HPDF_REAL value);
__declspec(dllimport) HPDF_STATUS
HPDF_Stream_Write (HPDF_Stream stream,
const HPDF_BYTE *ptr,
HPDF_UINT size);
__declspec(dllimport) HPDF_STATUS
HPDF_Stream_Read (HPDF_Stream stream,
HPDF_BYTE *ptr,
HPDF_UINT *size);
__declspec(dllimport) HPDF_STATUS
HPDF_Stream_ReadLn (HPDF_Stream stream,
char *s,
HPDF_UINT *size);
__declspec(dllimport) HPDF_INT32
HPDF_Stream_Tell (HPDF_Stream stream);
__declspec(dllimport) HPDF_STATUS
HPDF_Stream_Seek (HPDF_Stream stream,
HPDF_INT pos,
HPDF_WhenceMode mode);
__declspec(dllimport) HPDF_BOOL
HPDF_Stream_EOF (HPDF_Stream stream);
__declspec(dllimport) HPDF_UINT32
HPDF_Stream_Size (HPDF_Stream stream);
__declspec(dllimport) HPDF_STATUS
HPDF_Stream_Flush (HPDF_Stream stream);
__declspec(dllimport) HPDF_STATUS
HPDF_Stream_WriteEscapeName (HPDF_Stream stream,
const char *value);
__declspec(dllimport) HPDF_STATUS
HPDF_Stream_WriteEscapeText2 (HPDF_Stream stream,
const char *text,
HPDF_UINT len);
__declspec(dllimport) HPDF_STATUS
HPDF_Stream_WriteEscapeText (HPDF_Stream stream,
const char *text);
__declspec(dllimport) HPDF_STATUS
HPDF_Stream_WriteBinary (HPDF_Stream stream,
const HPDF_BYTE *data,
HPDF_UINT len,
HPDF_Encrypt e);
__declspec(dllimport) HPDF_STATUS
HPDF_Stream_Validate (HPDF_Stream stream);
#ifdef __cplusplus
}
#endif __cplusplus
#endif _HPDF_STREAMS_H
以下是导致链接错误的调用函数：
void CPDF2View::OnInitialUpdate()
{
CView::OnInitialUpdate();
AfxGetMainWnd()->ActivateTopParent();
HPDF_Doc pdf;
pdf = HPDF_New(error_handler, NULL);
HPDF_Page page_1;
page_1 = HPDF_AddPage(pdf);
HPDF_SaveToFile(pdf, "test.pdf");
Invalidate(TRUE);
}
我使用 /VERBOSE 来诊断链接器输出，我得到了未使用 hpdflib.lib 的信息。某人可以解释什么是问题吗？