Import and export

Foxit PDF SDK for iOS imports and exports annotation data in FDF and XFDF formats for exchange between documents and systems. The SDK also flattens annotations into page content.

FDF and XFDF

Format	Constant	Description
FDF	FSFDFDocFDF	Forms Data Format (binary)
XFDF	FSFDFDocXFDF	XML FDF

FSFDFDoc APIs:

Method	Description
initWithType:	Create empty FDF (FSFDFDocFDF or FSFDFDocXFDF)
initWithPath:	Load from path
getType	Format type
isEmpty	Empty check
saveAs:	Save to file

Export annotations

Export all

[FSPDFDoc exportToFDFDoc:data_type:range:]:

#import <FoxitRDK/FSPDFObjC.h>

FSPDFDoc *doc = [[FSPDFDoc alloc] initWithPath:@"path/to/Sample.pdf"];
[doc load:nil];

FSFDFDoc *fdfDoc = [[FSFDFDoc alloc] initWithType:FSFDFDocXFDF];
[doc exportToFDFDoc:fdfDoc data_type:FSPDFDocAnnots range:nil];
[fdfDoc saveAs:@"path/to/annotations.xfdf"];

NOTE

data_type FSPDFDocAnnots exports annotations. range (FSRange) limits pages; nil exports all pages.

Export one annotation

[FSPDFDoc exportAnnotToFDFDoc:annot:]:

#import <FoxitRDK/FSPDFObjC.h>

FSPDFDoc *doc = [[FSPDFDoc alloc] initWithPath:@"path/to/Sample.pdf"];
[doc load:nil];
FSPDFPage *page = [doc getPage:0];

FSAnnot *annot = [page getAnnot:0];

FSFDFDoc *fdfDoc = [[FSFDFDoc alloc] initWithType:FSFDFDocFDF];
[doc exportAnnotToFDFDoc:fdfDoc annot:annot];
[fdfDoc saveAs:@"path/to/single_annot.fdf"];

Import annotations

[FSPDFDoc importFromFDFDoc:data_type:range:]:

#import <FoxitRDK/FSPDFObjC.h>

FSPDFDoc *doc = [[FSPDFDoc alloc] initWithPath:@"path/to/Sample.pdf"];
[doc load:nil];

FSFDFDoc *fdfDoc = [[FSFDFDoc alloc] initWithPath:@"path/to/annotations.xfdf"];

[doc importFromFDFDoc:fdfDoc data_type:FSPDFDocAnnots range:nil];

[doc saveAs:@"path/to/output.pdf" saveFlags:FSPDFDocSaveFlagNormal];

Flatten annotations

Flattening merges annotation appearance into page content and removes the annotation objects (no longer selectable or editable).

Flatten all on a page

#import <FoxitRDK/FSPDFObjC.h>

FSPDFDoc *doc = [[FSPDFDoc alloc] initWithPath:@"path/to/Sample.pdf"];
[doc load:nil];
FSPDFPage *page = [doc getPage:0];

[page flattenAnnots:YES];

[doc saveAs:@"path/to/flattened.pdf" saveFlags:FSPDFDocSaveFlagNormal];

NOTE

YES flattens all annotations; NO flattens form fields only.

Flatten one annotation

FSPDFPage *page = [doc getPage:0];
FSAnnot *annot = [page getAnnot:0];

if (annot && ![annot isEmpty]) {
    [page flattenAnnot:annot];
}

Typical scenarios

Scenario	Approach
Collaborative review — share annotations	Export XFDF, distribute, import locally
Server-side annotation processing	XFDF for parsing and storage
Final publish — non-editable annotations	Export backup, then flatten all
Archival — consistent rendering	Flatten annotations and form fields