magento 2 issetflag ()
$path = 'path/to/value';
$value = $this->scopeConfig->getValue($path, \Magento\Store\Model\ScopeInterface::SCOPE_STORE);
Lazy Lapwing
$path = 'path/to/value';
$value = $this->scopeConfig->getValue($path, \Magento\Store\Model\ScopeInterface::SCOPE_STORE);
$flag = $this->scopeConfig->isSetFlag($path, \Magento\Store\Model\ScopeInterface::SCOPE_STORE);