framework/requirements/YiiRequirementChecker.php
function checkPhpExtensionVersion($extensionName, $version, $compare = '>=')
    {
        if (!extension_loaded($extensionName)) {
            return false;
        }
        $extensionVersion = phpversion($extensionName);
        if (empty($extensionVersion)) {
            return false;
        }
        if (strncasecmp($extensionVersion, 'PECL-', 5) === 0) {
            $extensionVersion = substr($extensionVersion, 5);
        }

        return version_compare($extensionVersion, $version, $compare);
    }
function checkPhpExtensionVersion($extensionName, $version, $compare = '>=')
    {
        if (!extension_loaded($extensionName)) {
            return false;
        }
        $extensionVersion = phpversion($extensionName);
        if (empty($extensionVersion)) {
            return false;
        }
        if (strncasecmp($extensionVersion, 'PECL-', 5) === 0) {
            $extensionVersion = substr($extensionVersion, 5);
        }

        return version_compare($extensionVersion, $version, $compare);
    }
Checks if the given PHP extension is available and its version matches the given one.
@param string $extensionName PHP extension name.
@param string $version required PHP extension version.
@param string $compare comparison operator, by default '>='
@return bool if PHP extension version matches.