contenttype pdf with code examples

from reportlab.lib.pagesizes import letter
from reportlab.pdfgen import canvas

def create_pdf(file_name):
    c = canvas.Canvas(file_name, pagesize=letter)
    c.drawString(100, 750, "Hello, World!")
    c.save()

create_pdf("hello_world.pdf")

import com.itextpdf.kernel.pdf.PdfDocument;
import com.itextpdf.kernel.pdf.PdfWriter;
import com.itextpdf.layout.Document;
import com.itextpdf.layout.element.Paragraph;

public class CreatePDF {
    public static void main(String[] args) {
        PdfWriter writer = new PdfWriter("hello_world.pdf");
        PdfDocument pdf = new PdfDocument(writer);
        Document document = new Document(pdf);
        document.add(new Paragraph("Hello, World!"));
        document.close();
    }
}

var pdfmake = require('pdfmake/build/pdfmake.js');
var pdfFonts = require('pdfmake/build/vfs_fonts.js');
pdfmake.vfs = pdfFonts.pdfMake.vfs;

var docDefinition = {
    content: [
        'Hello, World!'
    ]
};

pdfmake.createPdf(docDefinition).download('hello_world.pdf');

import PyPDF2

def read_pdf(file_name):
    with open(file_name, 'rb') as f:
        pdf = PyPDF2.PdfFileReader(f)
        for page in range(pdf.getNumPages()):
            print(pdf.getPage(page).extractText())

read_pdf("hello_world.pdf")

import PyPDF2

def merge_pdfs(file_names, output_file):
    pdf_merger = PyPDF2.PdfFileMerger()
    for file_name in file_names:
        with open(file_name, 'rb') as f:
            pdf_merger.append(f)
    with open(output_file, 'wb') as f:
        pdf_merger.write(f)

merge_pdfs(["file1.pdf", "file2.pdf"], "merged.pdf")

import com.itextpdf.kernel.pdf.PdfDocument;
import com.itextpdf.kernel.pdf.PdfReader;
import com.itextpdf.kernel.pdf.PdfWriter;
import com.itextpdf.layout.Document;
import com.itextpdf.layout.element.Paragraph;

public class EditPDF {
    public static void main(String[] args) {
        PdfReader reader = new PdfReader("existing_file.pdf");
        PdfWriter writer = new PdfWriter("modified_file.pdf");
        PdfDocument pdf = new PdfDocument(reader, writer);
        Document document = new Document(pdf);
        document.add(new Paragraph("This text was added programmatically."));
        document.close();
    }
}

var pdfmake = require('pdfmake/build/pdfmake.js');
var pdfFonts = require('pdfmake/build/vfs_fonts.js');
pdfmake.vfs = pdfFonts.pdfMake.vfs;

var docDefinition = {
    content: [
        { text: 'Hello, World!', style: 'header' },
        {
            style: 'tableExample',
            table: {
                widths: [100, '*', 200, '*'],
                body: [
                    [{ text: 'Header 1', style: 'tableHeader' }, { text: 'Header 2', style: 'tableHeader' }, { text: 'Header 3', style: 'tableHeader' }, { text: 'Header 4', style: 'tableHeader' }],
                    [ 'Sample value 1', 'Sample value 2', 'Sample value 3', 'Sample value 4'],
                    [ 'Sample value 5', 'Sample value 6', 'Sample value 7', 'Sample value 8'],
                    [ '
## Popular questions 
1. What is PDF and what are its uses?

PDF, or Portable Document Format, is a file format that is used to present documents in a manner that is independent of the application software, hardware, and operating system used to create them. PDF files can contain text, images, videos, and other multimedia elements, as well as interactive features such as buttons and form fields. They are commonly used for creating and sharing documents such as resumes, invoices, and e-books.

2. How can I create a PDF file programmatically?

There are several libraries available for creating PDF files programmatically in different programming languages. For example, in Python, the most popular library for creating PDF files is ReportLab, in Java the most popular library for creating PDF files is iText, and in JavaScript, the most popular library for creating PDF files is pdfmake. Each library has its own set of methods for creating PDF files and adding content to them.

3. How can I read the contents of a PDF file programmatically?

Just as there are libraries for creating PDF files, there are also libraries for reading and parsing PDF files. For example, in Python, one popular library for reading PDF files is PyPDF2, in Java the most popular library for reading PDF files is Apache PDFBox and in JavaScript, the most popular library for reading PDF files is pdfjs-dist. Each library has its own set of methods for reading and parsing PDF files and extracting their contents.

4. How can I edit a PDF file programmatically?

Once you have read the contents of a PDF file, you may want to edit it in some way. There are several libraries available for editing PDF files programmatically in different programming languages. For example, in Python, the PyPDF2 library can be used to merge, split, and crop pages, as well as add and remove text and images. In Java, the iText library can be used to add and remove text, images and shapes, as well as manipulate the layout and formatting. In JavaScript, the pdfmake library can be used to manipulate the content and layout, as well as add interactive features such as buttons and form fields.

5. What are some common use cases for working with PDF files programmatically?

There are many use cases for working with PDF files programmatically, including: 
- Automating the creation of PDF documents, such as invoices, resumes, and e-books. 
- Extracting data from PDF files for use in other applications, such as data entry or analytics. 
- Modifying existing PDF files, such as adding or removing pages, or editing the content and layout. 
- Programmatically filling out PDF forms and generating PDFs from templates.
- Building PDF viewer or editor applications.

### Tag 
PDFProgramming