Objective-C Requires Chilkat v11.7.0+

Why a PDF Text Replacement Is Refused: the Font Rule

See more PDF Text Replacement Examples

A PDF stores glyphs drawn with particular fonts, so new text can only be drawn when the original font can draw it. This example shows the two common refusals. A font embedded as a subset carries only the glyphs the document used: a value made of other characters is refused with the reason missingGlyph, and the report names the font and the characters it lacks. A font that is neither one of the standard 14 nor embedded (here Verdana) is refused with nonStandardUnembeddedFont, because Chilkat cannot know what a viewer will draw for it. A non-embedded Arial, Times New Roman or Courier New is treated as the standard font every viewer substitutes for it. 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 quote_subset_font.pdf
//  and letter_verdana.pdf

//  1. An embedded subset font: only the glyphs the document uses are in the PDF.
CkoPdf *pdf = [[CkoPdf alloc] init];
success = [pdf LoadFile: @"qa_data/pdf/quote_subset_font.pdf"];
if (success == NO) {
    NSLog(@"%@",pdf.LastErrorText);
    return;
}

CkoJsonObject *json = [[CkoJsonObject alloc] init];
CkoJsonObject *jsonOut = [[CkoJsonObject alloc] init];

//  The regular face's subset carries the characters of the quotation's text, among them the digits of
//  "58341".  A new number made of those digits can be drawn...
[json UpdateString: @"labels[0].label" value: @"Quote #:"];
[json UpdateString: @"labels[0].value" value: @"58314"];
success = [pdf TextReplace: @"check" jsonIn: json jsonOut: jsonOut];
if (success == NO) {
    NSLog(@"%@",pdf.LastErrorText);
    return;
}

NSLog(@"%@%d",@"58314: ok = ",[jsonOut BoolOf: @"ok"]);

//  ...but "Q" and "-" are not in the subset (nothing in the quotation's regular text uses them).
[json UpdateString: @"labels[0].value" value: @"Q-58341"];
success = [pdf TextReplace: @"check" jsonIn: json jsonOut: jsonOut];
if (success == NO) {
    NSLog(@"%@",pdf.LastErrorText);
    return;
}

NSLog(@"%@%d",@"Q-58341: ok = ",[jsonOut BoolOf: @"ok"]);
if ([jsonOut BoolOf: @"ok"] == NO) {
    //  The problem names the font and the characters it cannot draw.
    NSLog(@"%@%@",@"    reason: ",[jsonOut StringOf: @"problems[0].reason"]);
    NSLog(@"%@%@",@"    font: ",[jsonOut StringOf: @"problems[0].font"]);
    NSLog(@"%@%@",@"    missing: ",[jsonOut StringOf: @"problems[0].chars"]);
}

//  "apply" with a problem returns false and changes nothing.
success = [pdf TextReplace: @"apply" jsonIn: json jsonOut: jsonOut];
NSLog(@"%@%d%@%d",@"apply returned ",success,@", applied = ",[jsonOut BoolOf: @"applied"]);

//  2. A font that is not embedded and not one of the standard 14.
CkoPdf *pdf2 = [[CkoPdf alloc] init];
success = [pdf2 LoadFile: @"qa_data/pdf/letter_verdana.pdf"];
if (success == NO) {
    NSLog(@"%@",pdf2.LastErrorText);
    return;
}

CkoJsonObject *json2 = [[CkoJsonObject alloc] init];
[json2 UpdateString: @"labels[0].label" value: @"Account Number:"];
[json2 UpdateString: @"labels[0].value" value: @"0000099999"];
success = [pdf2 TextReplace: @"check" jsonIn: json2 jsonOut: jsonOut];
if (success == NO) {
    NSLog(@"%@",pdf2.LastErrorText);
    return;
}

NSLog(@"%@%d%@%@%@%@",@"Verdana, not embedded: ok = ",[jsonOut BoolOf: @"ok"],@", reason: ",[jsonOut StringOf: @"problems[0].reason"],@", font: ",[jsonOut StringOf: @"problems[0].font"]);

//  Sample output:

//  58314: ok = true
//  Q-58341: ok = false
//      reason: missingGlyph
//      font: AAAAAA+DejaVuSans
//      missing: Q-
//  apply returned false, applied = false
//  Verdana, not embedded: ok = false, reason: nonStandardUnembeddedFont, font: Verdana