外壳 (Wrapper)

Wrapper 为用户提供了一种保存与 PDF 文档相关的数据的方法。例如，在打开一个加密未授权的 PDF 文档，用户会看到错误信息提示其没有权限访问该文档。在这种情况下，使用 wrapper，用户即使无法访问 PDF 中的内容，但仍然可以访问该文档的 wrapper 数据。Wrapper 数据可用来提供信息给用户，比如文档的解密方法。

打开包含 wrapper 数据的 PDF 文档

c++

#include "include/common/fs_common.h"
#include "include/pdf/fs_pdfdoc.h"
#include "include/pdf/fs_pdfpage.h"
#include "include/common/fs_render.h"

using namespace foxit;
using namespace foxit::common;
using foxit::common::Library;
using namespace pdf;
using namespace common::file;

// file_name is PDF document which includes wrapper data.
PDFDoc doc(file_name);
ErrorCode code = doc.Load();
if (code != foxit::e_ErrSuccess) {
    return false;
}
if(!doc.IsWrapper()){
    return false;
}
int64 offset = doc.GetWrapperOffset();

FileReader file_reader(offset);
file_reader.LoadFile(String::FromUnicode(file_name));
...

C

#include "include/fs_basictypes_c.h"
#include "include/fs_common_c.h"
#include "include/fs_pdfdoc_c.h"
#include "include/fs_pdfpage_c.h"
#include "include/fs_render_c.h"

// file_name is PDF document which includes wrapper data.
FS_PDFDOC_HANDLE doc;
FSDK_PDFDoc_Create0(input_file, &doc);
FSErrorCode code = FSDK_PDFDoc_Load(doc_wrapper, NULL);
if (e_FSErrSuccess) {
    FSDK_PDFDoc_Release(doc); 
    return false;
}
FS_BOOL return_iswrapper;
FSDK_PDFDoc_IsWrapper(doc, &return_iswrapper);
if(!return_iswrapper){
    return false;
}
FS_INT64 offset;
FSDK_PDFDoc_GetWrapperOffset(doc, &offset);

FileReader file_reader(offset);
file_reader.LoadFile(file_name);
...

java

import com.foxit.sdk.common.fxcrt.FileReaderCallback;

import com.foxit.sdk.pdf.PDFDoc;
import com.foxit.sdk.pdf.WrapperData;
...

PDFDoc doc = new PDFDoc(file_name);
int code = doc.load(null);
if (code != e_ErrSuccess) {
    return;
}
if (!doc.isWrapper()) {
    return;
}
int offset = doc.getWrapperOffset();
FileReader file_reader = new FileReader(offset);
file_reader.LoadFile(file_name);

PDFDoc doc_real = new PDFDoc(file_reader, false);
code = doc_real.load(null);
if (code != e_ErrSuccess) {
    return;
}
...

py

import sys
import site

if sys.version_info.major == 2:
    _PYTHON2_ = True
else:
    _PYTHON2_ = False

if _PYTHON2_:
    #replace with the python2 lib path
    site.addsitedir('../../../')
    from FoxitPDFSDKPython2 import *
else:
    from FoxitPDFSDKPython3 import *
# file_name is PDF document which includes wrapper data.
doc = PDFDoc(file_name)
code = doc.Load()
if code != e_ErrSuccess:
    return False

if not doc.IsWrapper():
    return False

offset = doc.GetWrapperOffset()

file_reader = FileReader(offset)
file_reader.LoadFile(file_name)
...

objc

#include "FSPDFObjC.h"
...

FSPDFDoc *doc = [[FSPDFDoc alloc] initWithPath:file_name];
FSErrorCode code = [doc load:nil];
if (code != FSErrSuccess) {
    return -1;
}
if (![doc isWrapper]) {
    return -1;
}
long long offset = [doc getWrapperOffset];
FSFileRead *file_reader = [[FSFileRead alloc] initWithSourceFilePath:file_name offset:offset];

FSPDFDoc *doc_real = [[FSPDFDoc alloc] initWithFile_read:file_reader is_async:NO];
code = [doc_real load:nil];
if (code != FSErrSuccess) {
    return -1;
}	
...

js

const FSDK = require("@foxitsoftware/foxit-pdf-sdk-node");
// file_name is PDF document which includes wrapper data.
let doc = new FSDK.PDFDoc(file_name);
let code = doc.Load("");
if (code != FSDK.e_ErrSuccess) {
    return false;
}

  if(!doc.IsWrapper()){
    return false;
  }

let offset = doc.GetWrapperOffset();

let file_reader = new FileReader(offset);
file_reader.LoadFile(file_name);
let reader_callback = new FSDK.FileReaderCallback(file_reader);
...

csharp

using foxit;
using foxit.common;
using foxit.common.fxcrt;
using foxit.pdf;
using foxit.pdf.graphics;
using foxit.pdf.objects;

// Assuming PDFDoc doc has been loaded.
 
// file_name is PDF document which includes wrapper data.
PDFDoc doc = new PDFDoc(file_name);
ErrorCode code = doc.Load(null);
if (code != ErrorCode.e_ErrSuccess)
{
return;
}
if (!doc.IsWrapper())
{
return;
}

long offset = doc.GetWrapperOffset();
FileReader file_reader = new FileReader(offset);
file_reader.LoadFile(file_name);
...