core-bundle/src/Resources/contao/classes/Versions.php
public function renderDropdown()
	{
		$objVersion = $this->Database->prepare("SELECT tstamp, version, username, active FROM tl_version WHERE fromTable=? AND pid=? ORDER BY version DESC")
								     ->execute($this->strTable, $this->intPid);

		if ($objVersion->numRows < 2)
		{
			return '';
		}

		$versions = '';

		while ($objVersion->next())
		{
			$versions .= '
  <option value="'.$objVersion->version.'"'.($objVersion->active ? ' selected="selected"' : '').'>'.$GLOBALS['TL_LANG']['MSC']['version'].' '.$objVersion->version.' ('.Date::parse(Config::get('datimFormat'), $objVersion->tstamp).') '.$objVersion->username.'</option>';
		}

		return '
<div class="tl_version_panel">

<form action="'.ampersand(Environment::get('request'), true).'" id="tl_version" class="tl_form" method="post" aria-label="'.StringUtil::specialchars($GLOBALS['TL_LANG']['MSC']['versioning']).'">
<div class="tl_formbody">
<input type="hidden" name="FORM_SUBMIT" value="tl_version">
<input type="hidden" name="REQUEST_TOKEN" value="'.REQUEST_TOKEN.'">
<select name="version" class="tl_select">'.$versions.'
</select>
<button type="submit" name="showVersion" id="showVersion" class="tl_submit">'.$GLOBALS['TL_LANG']['MSC']['restore'].'</button>
<a href="'.Backend::addToUrl('versions=1&amp;popup=1').'" title="'.StringUtil::specialchars($GLOBALS['TL_LANG']['MSC']['showDifferences']).'" onclick="Backend.openModalIframe({\'title\':\''.StringUtil::specialchars(str_replace("'", "\\'", sprintf($GLOBALS['TL_LANG']['MSC']['recordOfTable'], $this->intPid, $this->strTable))).'\',\'url\':this.href});return false">'.Image::getHtml('diff.svg').'</a>
</div>
</form>

</div>
';
	}
public function renderDropdown()
	{
		$objVersion = $this->Database->prepare("SELECT tstamp, version, username, active FROM tl_version WHERE fromTable=? AND pid=? ORDER BY version DESC")
								     ->execute($this->strTable, $this->intPid);

		if ($objVersion->numRows < 2)
		{
			return '';
		}

		$versions = '';

		while ($objVersion->next())
		{
			$versions .= '
  <option value="'.$objVersion->version.'"'.($objVersion->active ? ' selected="selected"' : '').'>'.$GLOBALS['TL_LANG']['MSC']['version'].' '.$objVersion->version.' ('.Date::parse(Config::get('datimFormat'), $objVersion->tstamp).') '.$objVersion->username.'</option>';
		}

		return '
<div class="tl_version_panel">

<form action="'.ampersand(Environment::get('request'), true).'" id="tl_version" class="tl_form" method="post" aria-label="'.StringUtil::specialchars($GLOBALS['TL_LANG']['MSC']['versioning']).'">
<div class="tl_formbody">
<input type="hidden" name="FORM_SUBMIT" value="tl_version">
<input type="hidden" name="REQUEST_TOKEN" value="'.REQUEST_TOKEN.'">
<select name="version" class="tl_select">'.$versions.'
</select>
<button type="submit" name="showVersion" id="showVersion" class="tl_submit">'.$GLOBALS['TL_LANG']['MSC']['restore'].'</button>
<a href="'.Backend::addToUrl('versions=1&amp;popup=1').'" title="'.StringUtil::specialchars($GLOBALS['TL_LANG']['MSC']['showDifferences']).'" onclick="Backend.openModalIframe({\'title\':\''.StringUtil::specialchars(str_replace("'", "\\'", sprintf($GLOBALS['TL_LANG']['MSC']['recordOfTable'], $this->intPid, $this->strTable))).'\',\'url\':this.href});return false">'.Image::getHtml('diff.svg').'</a>
</div>
</form>

</div>
';
	}
Render the versions dropdown menu

@return string