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. C

#include <C_CkPdf.h>
#include <C_CkJsonObject.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkPdf pdf;
    HCkJsonObject json;
    HCkJsonObject jsonOut;
    HCkPdf pdf2;
    HCkJsonObject json2;

    success = FALSE;

    //  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.
    pdf = CkPdf_Create();
    success = CkPdf_LoadFile(pdf,"qa_data/pdf/quote_subset_font.pdf");
    if (success == FALSE) {
        printf("%s\n",CkPdf_lastErrorText(pdf));
        CkPdf_Dispose(pdf);
        return;
    }

    json = CkJsonObject_Create();
    jsonOut = CkJsonObject_Create();

    //  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...
    CkJsonObject_UpdateString(json,"labels[0].label","Quote #:");
    CkJsonObject_UpdateString(json,"labels[0].value","58314");
    success = CkPdf_TextReplace(pdf,"check",json,jsonOut);
    if (success == FALSE) {
        printf("%s\n",CkPdf_lastErrorText(pdf));
        CkPdf_Dispose(pdf);
        CkJsonObject_Dispose(json);
        CkJsonObject_Dispose(jsonOut);
        return;
    }

    printf("58314: ok = %d\n",CkJsonObject_BoolOf(jsonOut,"ok"));

    //  ...but "Q" and "-" are not in the subset (nothing in the quotation's regular text uses them).
    CkJsonObject_UpdateString(json,"labels[0].value","Q-58341");
    success = CkPdf_TextReplace(pdf,"check",json,jsonOut);
    if (success == FALSE) {
        printf("%s\n",CkPdf_lastErrorText(pdf));
        CkPdf_Dispose(pdf);
        CkJsonObject_Dispose(json);
        CkJsonObject_Dispose(jsonOut);
        return;
    }

    printf("Q-58341: ok = %d\n",CkJsonObject_BoolOf(jsonOut,"ok"));
    if (CkJsonObject_BoolOf(jsonOut,"ok") == FALSE) {
        //  The problem names the font and the characters it cannot draw.
        printf("    reason: %s\n",CkJsonObject_stringOf(jsonOut,"problems[0].reason"));
        printf("    font: %s\n",CkJsonObject_stringOf(jsonOut,"problems[0].font"));
        printf("    missing: %s\n",CkJsonObject_stringOf(jsonOut,"problems[0].chars"));
    }

    //  "apply" with a problem returns false and changes nothing.
    success = CkPdf_TextReplace(pdf,"apply",json,jsonOut);
    printf("apply returned %d, applied = %d\n",success,CkJsonObject_BoolOf(jsonOut,"applied"));

    //  2. A font that is not embedded and not one of the standard 14.
    pdf2 = CkPdf_Create();
    success = CkPdf_LoadFile(pdf2,"qa_data/pdf/letter_verdana.pdf");
    if (success == FALSE) {
        printf("%s\n",CkPdf_lastErrorText(pdf2));
        CkPdf_Dispose(pdf);
        CkJsonObject_Dispose(json);
        CkJsonObject_Dispose(jsonOut);
        CkPdf_Dispose(pdf2);
        return;
    }

    json2 = CkJsonObject_Create();
    CkJsonObject_UpdateString(json2,"labels[0].label","Account Number:");
    CkJsonObject_UpdateString(json2,"labels[0].value","0000099999");
    success = CkPdf_TextReplace(pdf2,"check",json2,jsonOut);
    if (success == FALSE) {
        printf("%s\n",CkPdf_lastErrorText(pdf2));
        CkPdf_Dispose(pdf);
        CkJsonObject_Dispose(json);
        CkJsonObject_Dispose(jsonOut);
        CkPdf_Dispose(pdf2);
        CkJsonObject_Dispose(json2);
        return;
    }

    printf("Verdana, not embedded: ok = %d, reason: %s, font: %s\n",CkJsonObject_BoolOf(jsonOut,"ok"),CkJsonObject_stringOf(jsonOut,"problems[0].reason"),CkJsonObject_stringOf(jsonOut,"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


    CkPdf_Dispose(pdf);
    CkJsonObject_Dispose(json);
    CkJsonObject_Dispose(jsonOut);
    CkPdf_Dispose(pdf2);
    CkJsonObject_Dispose(json2);

    }