framework/base/Model.php
public function getFirstError($attribute)
    {
        return isset($this->_errors[$attribute]) ? reset($this->_errors[$attribute]) : null;
    }
public function getFirstError($attribute)
    {
        return isset($this->_errors[$attribute]) ? reset($this->_errors[$attribute]) : null;
    }
Returns the first error of the specified attribute.
@param string $attribute attribute name.
@return string the error message. Null is returned if no error.
@see getErrors()
@see getFirstErrors()