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SmartString: PHP Strings That HTML-Encode Themselves

SmartString lets you write template code that’s shorter, easier to read, and XSS-safe by default. Values HTML-encode themselves the moment you echo, interpolate, or concatenate them, so one forgotten htmlspecialchars() can’t become an injection.

Instead of writing code like this:

echo "<h1>" . htmlspecialchars($article['title'], ENT_QUOTES|ENT_SUBSTITUTE|ENT_HTML5, 'UTF-8') . "</h1>";
$summary = strip_tags($article['content']); // remove tags
$summary = html_entity_decode($summary, ENT_QUOTES|ENT_SUBSTITUTE|ENT_HTML5, 'UTF-8'); // decode entities
$summary = substr($summary, 0, 120); // limit to 120 characters
echo "Summary: " . htmlspecialchars($summary, ENT_QUOTES|ENT_SUBSTITUTE|ENT_HTML5, 'UTF-8') . "...";

You can write code like this:

echo "<h1>$article->title</h1>";
echo "Summary: {$article->content->textOnly()->maxChars(120, '...')}\n";

SmartString encodes HTML output automatically and includes utility functions for common template tasks.

Full guides and references (browse on GitHub):

  • The Basics (read in order)
  • Everyday Use
  • Lookup
    • Method Reference - every method, grouped by what it returns
    • Troubleshooting - common error messages and gotchas, with fixes
    • Performance - how our automatic encoding is at least 3x faster than calling htmlspecialchars() yourself
    • AI Reference - the complete API in one dense file, written for AI coding assistants

Use SmartString where it makes your code simpler, and plain PHP where you prefer it. The original value is always one call away:

// SmartString: ->value() returns the original value, in its original type
$name = $user->name->value();
// SmartArray (companion library): ->toArray() returns a plain nested array
$rows = $orders->toArray();
  • SmartArray - database rows as chainable collections, with fields returned as SmartStrings.
  • ZenDB - database library that returns query results as SmartArrays of SmartStrings, so fields arrive HTML-safe.

This library was developed for CMS Builder. Post a message in our “CMS Builder” forum here: https://www.interactivetools.com/forum/

MIT