Creare un file PDF con le funzioni esterne della libreria PDFGen

Mostriamo un semplice esempio pratico per generare un file PDF:

Library "/tmp/libPDFGen"

Private Const PDF_A4_WIDTH As Single = 210.0
Private Const PDF_A4_HEIGHT As Single = 297.0
Private Const PDF_A3_WIDTH As Single = 297.0
Private Const PDF_A3_HEIGHT As Single = 420.0

Private Enum PDF_ALIGN_LEFT, PDF_ALIGN_RIGHT, PDF_ALIGN_CENTER, PDF_ALIGN_JUSTIFY, PDF_ALIGN_JUSTIFY_ALL, PDF_ALIGN_NO_WRITE

' struct pdf_doc *pdf_create(float width, float height, const struct pdf_info *info)
' Create a new PDF object, with the given page width/height.
Private Extern pdf_create(width As Single, height As Single, info As Pointer) As Pointer

' int pdf_set_font(struct pdf_doc *pdf, const char *font)
' Sets the font to use for text objects.
Private Extern pdf_set_font(pdf As Pointer, __font As String) As Integer

' struct pdf_object *pdf_append_page(struct pdf_doc *pdf)
' Add a new page to the given pdf.
Private Extern pdf_append_page(pdf As Pointer) As Pointer

' int pdf_add_text(struct pdf_doc *pdf, struct pdf_object *page, const char *text, float size, float xoff, float yoff, uint32_t colour)
' Add a text string to the document.
Private Extern pdf_add_text(pdf As Pointer, page As Pointer, text As String, size As Single, xoff As Single, yoff As Single, colour As Integer) As Integer

' int pdf_add_text_wrap(struct pdf_doc *pdf, struct pdf_object *page, const char *text, float size, float xoff, float yoff, uint32_t colour, float wrap_width, int align, float *height)
' Add a text string to the document, making it wrap if it is too long.
Private Extern pdf_add_text_wrap(pdf As Pointer, page As Pointer, text As String, size As Single, xoff As Single, yoff As Single, colour As Integer, wrap_width As Single, align As Integer, height As Pointer) As Integer

' int pdf_add_image_file(struct pdf_doc *pdf, struct pdf_object *page, float x, float y, float display_width, float display_height, const char *image_filename) As Integer
' Add an image file as an image to the document.
Private Extern pdf_add_image_file(pdf As Pointer, page As Pointer, x As Single, y As Single, display_width As Single, display_height As Single, image_filename As String) As Integer

' int pdf_add_line(struct pdf_doc *pdf, struct pdf_object *page, float x1, float y1, float x2, float y2, float width, uint32_t colour)
' Add a line to the document.
Private Extern pdf_add_line(pdf As Pointer, page As Pointer, x1 As Single, y1 As Single, x2 As Single, y2 As Single, width As Single, colour As Integer) As Integer

' int pdf_save(struct pdf_doc *pdf, const char *filename)
' Save the given pdf document to the supplied filename.
Private Extern pdf_save(pdf As Pointer, filename As String) As Integer

' void pdf_destroy(struct pdf_doc *pdf)
' Destroy the pdf object, and all of its associated memory.
Private Extern pdf_destroy(pdf As Pointer)


Public Sub Main()

 Dim pdfdoc As Pointer
 Dim height As Single

 File.save("/tmp/pdfgen.h", HttpClient.Download("https://raw.githubusercontent.com/AndreRenaud/PDFGen/master/pdfgen.h"))
 File.save("/tmp/pdfgen.c", HttpClient.Download("https://raw.githubusercontent.com/AndreRenaud/PDFGen/master/pdfgen.c"))
 File.Save("/tmp/pdfgen.c", Replace(File.Load("/tmp/pdfgen.c"), "pdfgen.h", "/tmp/pdfgen.h"))

 If Not Exist("/tmp/libPDFGen.so") Then Creaso()
 
 pdfdoc = pdf_create(MMtoPoint(PDF_A4_WIDTH), MMtoPoint(PDF_A4_HEIGHT), 0)
 
 pdf_set_font(pdfdoc, "Times-Roman")
 
 pdf_append_page(pdfdoc)
 
 pdf_add_text(pdfdoc, 0, "Questa è la prima riga di testo.", 24, 50, 700, &000000)
 pdf_add_text(pdfdoc, 0, "Questa è la seconda riga di testo.", 12, 50, 680, &000000)
 
 pdf_add_line(pdfdoc, 0, 50, 600, 400, 600, 3, &00FF00)

 Print pdf_add_text_wrap(pdfdoc, 0, File.Load("/percorso/di/un/file/di/testo"), 12, 20, 350, &FF0000, MMtoPoint(PDF_A4_WIDTH) - 40, PDF_ALIGN_JUSTIFY, VarPtr(height))

 pdf_add_image_file(pdfdoc, 0, 100, 400, 150, 150, "/home/ploppo/Immagini/images.png")

 pdf_save(pdfdoc, "/tmp/output.pdf")
  
 pdf_destroy(pdfdoc)

End

Private Function MMtoPoint(mm As Single) As Single

 Return (mm * 72.0 / 25.4)

End

Private Procedure Creaso()

 Shell "gcc -o /tmp/libPDFGen.so /tmp/pdfgen.c -shared -fPIC" Wait
 
End

Pagina in costruzione !