Objective-C Requires Chilkat v11.7.0+

Tile a Watermark Across a PDF Page

See more PDF Watermark Examples

Demonstrates a tiled watermark, which repeats the stamp over the whole page instead of placing it once. Tiling overrides position.align; tile.spacingX and spacingY set the gaps, and tile.stagger offsets alternate rows by half a tile so the pattern does not line up in columns. A faint tiled stamp carrying the name or address is the usual way to mark a document so that a leaked copy can be traced back, and zOrder back keeps it behind the text where it does not hinder reading. Objective-C

#import <CkoPdf.h>
#import <CkoJsonObject.h>

BOOL success = NO;

//  This example requires the Chilkat API to have been previously unlocked.
//  See Global Unlock Sample for sample code.

//  The PDF used in this example is available at long_report.pdf

CkoPdf *pdf = [[CkoPdf alloc] init];
success = [pdf LoadFile: @"qa_data/pdf/long_report.pdf"];
if (success == NO) {
    NSLog(@"%@",pdf.LastErrorText);
    return;
}

CkoJsonObject *json = [[CkoJsonObject alloc] init];
[json UpdateString: @"type" value: @"text"];

//  {date:FORMAT} is replaced per page when the watermark is added.  The other placeholders are
//  {page}, {pages} and {filename}; {{ gives a literal brace.
[json UpdateString: @"text" value: @"jdoe@example.com  {date:yyyy-MM-dd}"];
[json UpdateString: @"id" value: @"trace"];
[json UpdateString: @"zOrder" value: @"back"];
[json UpdateNumber: @"font.size" numericStr: @"14"];
[json UpdateNumber: @"opacity" numericStr: @"0.15"];
[json UpdateNumber: @"rotation" numericStr: @"30"];

[json UpdateBool: @"tile.enabled" value: YES];
[json UpdateNumber: @"tile.spacingX" numericStr: @"60"];
[json UpdateNumber: @"tile.spacingY" numericStr: @"80"];
[json UpdateBool: @"tile.stagger" value: YES];

CkoJsonObject *jsonOut = [[CkoJsonObject alloc] init];
success = [pdf Watermark: @"add" jsonIn: json jsonOut: jsonOut];
if (success == NO) {
    NSLog(@"%@",pdf.LastErrorText);
    return;
}

NSLog(@"%@%@%@%@",@"id: ",[jsonOut StringOf: @"id"],@" pages: ",[jsonOut StringOf: @"pages"]);

success = [pdf WriteFile: @"qa_output/report_traced.pdf"];
if (success == NO) {
    NSLog(@"%@",pdf.LastErrorText);
    return;
}

//  Sample output:

//  id: trace pages: 1-3