Extending FPDF

If you are new to FPDF you may want to start by reading Part 1: Installation and Part 2: Playing with the options.

We can extend the core FPDF library and set up some functions that we can reuse. For example, we want to present a report in a table. The table will need column headings so that we know what each column of data represents. We could build that into the file for this one report, but say we want another report, different heading names but the same basic structure. We can either replicate the entire file from the other report and change the heading values or we can extend FPDF and create a tableHeader function that accepts an array of heading values and creates the header on the fly. This approach will save us time as we add new reports.

//include the core fpdf library
include 'fpdf/fpdf.php';

//create our custom class
class Myfpdf extends FPDF
{
	//takes an array of values and prints them as text headers with a black border around each one
       function tableHeader($header)
	{
		foreach($header as $col)
		{
			$this->Cell(38,7,$col,1,0,'L',0);
		}
		$this->Ln();
	}
}

Now we want to use this to create a pdf. So in our index.php file we need to set up some values and generate the pdf.

//include our custom fpdf class
include 'my.fpdf.php';

//instantiate the class
$myFPDF = new Myfpdf();

//create the pdf
$myFPDF->AddPage();
$myFPDF->setTitle('Title');
$myFPDF->setFont('Arial', 'B', 15);

//set up the Header values and call it
$myFPDF->tableHeader(array('Header 1', 'Header 2', 'Header 3', 'Header 4'));

echo $myFPDF->Output('test_header.pdf','I');

There you have it, a reusable table head builder. Now you can use the same concept as above to output the table data.

If you haven’t read part 1 of the series, you might want to start there.

Options

Today we are going to talk about the options we have when creating a pdf with the FPDF library. We will cover:

• Changing page orientation and size
• Changing Font styles
• Changing the size and style of text cells
• The different options for saving the final product

Changing page orientation and size

When we initiate the FPDF class we can specify the page orientation, unit of measure and size. Page orientations options are: Landscape (L) and Portrait (P). Next we can set the unit of measure (used for everything except font sizes): Point (pt), Millimeter (mm), Centimeter (cm), and inch (in). To specify page size we have many options along with the ability to specify our own custom size. The options are: A3, A4, A5, Letter, and Legal.

So if we want to create a legal sized PDF in the landscape format, using millimeters as our unit of measure this is what it looks like:

$fpdf = new FPDF('L', 'mm', 'Legal');

Say we want a custom sized page, we need to specify the width and height in an array. The width and height values will use the specified unit of measure. Here is an example:

$fpdf = new FPDF('L', 'mm', array('250','400'));

Our page will be 250 millimeters wide and 400 millimeters high.

Changing font styles

Next we want to set the font and its styles. According to the FPDF website the standard fonts available are: Arial, Times, Courier, Symbol, and ZapfDingbats. We will use Times for this example. Now we can set the font style, the options include: Italic (I), Bold (B), or Regular (empty string). You can also specify a combination of these styles. We will use bold. Last, we want to set the font size (always in points). For this example we will set it at 22 points.

So, our example would look like this:

$fpdf->SetFont('Times','B',22);

Note: This can be used on a line by line basis to change the font in a pdf.

Changing the size and style of text cells

Now we need to write some text to our pdf. To do this we use the Cell function. There are a lot of options available when writing a text cell: Width, Height, text you want printed, border, where the current position should go after this cell, text alignment, whether the cell should have a background color or not, and a link for the text. For a complete list of the variables see the manual at fpdf.org. We want to output our name in text that is centered on the page, with no border and we want the cell to go to the next line after writing our name.

So, our example would look like this:

$fpdf->Cell(0,0,'Our Name',0,1,'C');

I have found it handy to have the cell page of the manual open for reference while building my pdfs. It helps me keep the options straight.

The different options for saving the final product

We’ve got our document ready and now we need to save it. We can specify the name for the file (I have found it best to specify a name without spaces such as file_name instead of file name) and the destination of the document. We have four destinations available: Inline (I) to the browser, Download (D) with the browser, Save (F) to a local file, and return the document as a String (S).

So, our example would look like this:

$fpdf->Output('file_name','D');

Note: I have found “D” to be the most consistent option across the different browsers.

This concludes our lesson for today. I hope this helps you get started playing with the options!

We will be continuing the series soon by extending FPDF to save us time.

Read Part 3 – Extending & Reuse