Skip to content

Variables & Filters

Template variables are the simplest way to place application data into an ODT document.

Simple variables

Place a named placeholder in the LibreOffice template:

Customer: {{customer_name}}
Email: {{email}}

Assign the values from PHP:

$template->assign([
    'customer_name' => 'Jane Smith',
    'email' => 'JANE.SMITH@EXAMPLE.COM',
]);

Then render and save the document:

$template->render();
$template->save(__DIR__ . '/output/result.odt');

Multiple calls to assign() are allowed. Later values with the same key replace earlier assignments in the internal value set.

Filters

A filter transforms a value when the placeholder is rendered.

The general syntax is:

{{filter:name}}

Some filters accept an option:

{{filter:name|option}}

Text filters

{{upper:name}}
{{lower:email}}
{{trim:description}}
  • upper converts text to uppercase.
  • lower converts text to lowercase.
  • trim removes surrounding whitespace.

Date formatting

{{date:created_at|d.m.Y}}

The option is passed as a PHP date format. If no format is supplied, the engine uses d.m.Y.

Example:

$template->assign([
    'created_at' => '2026-08-24',
]);

With {{date:created_at|d.m.Y}}, the document receives 24.08.2026.

Number formatting

{{number:total|2}}

The option specifies the number of decimal places. The current formatter uses a comma as decimal separator and a dot as thousands separator.

Currency formatting

{{currency:total}}

The current currency filter formats the value with two decimal places and appends €.

Checkbox formatting

{{checkbox:approved}}

Truthy values render as ☑; falsy values render as ☐.

Line breaks with nl2br

Use nl2br when a value contains newline characters that should become native ODT line breaks:

{{nl2br:comment}}

$template->assign([
    'comment' => "First line\nSecond line",
]);

The engine inserts ODT <text:line-break/> elements rather than writing HTML <br> tags.

Keep placeholders easy to process

Office editors may split visually continuous text into multiple XML spans. The engine contains normalization logic for fragmented placeholders, but templates are more predictable when a placeholder remains one logical piece of text.

Prefer:

{{customer_name}}

and apply formatting to the whole placeholder or its paragraph rather than styling individual characters inside the marker.

Use assign() for normal values:

$template->assign([
    'name' => 'Jane Smith',
]);

Older direct assignment methods remain in the library for compatibility, but new application code and public samples should use the assign() → render() workflow.

Complete example

<?php

declare(strict_types=1);

require __DIR__ . '/vendor/autoload.php';

use OdtTemplateEngine\OdtTemplate;

$template = new OdtTemplate(__DIR__ . '/templates/customer.odt');

$template->assign([
    'name' => 'Jane Smith',
    'email' => 'JANE.SMITH@EXAMPLE.COM',
    'created_at' => '2026-08-24',
    'total' => '1345.5',
    'approved' => true,
]);

$template->render();
$template->save(__DIR__ . '/output/customer.odt');

A corresponding template could contain:

Customer: {{upper:name}}
Email: {{lower:email}}
Created: {{date:created_at|d.m.Y}}
Total: {{currency:total}}
Approved: {{checkbox:approved}}
  • L01 — Variables & Filters — canonical scalar assignment, formatting filters, and ODT line breaks
  • L02 — Conditions — canonical template-controlled conditional content
  • L03 — Repeating Content — canonical collection assignment and template repetition
  • B01 — larger business-document example combining template syntax and generated content

Continue with Conditions & Loops for conditional sections and repeating blocks.