How to override Registration success message magento 2?

Question

I am trying to override CreatePost.php in local but its not working properly. Below i am pasting the code please check once.

I am trying to override the code in getSuccessMessage function

C:\xampp\htdocs\magedemo\app\code\Vendor\Navdata\Controller\Account\CreatePost.php

<?php
    /**
     * Copyright © Magento, Inc. All rights reserved.
     * See COPYING.txt for license details.
     */
    namespace Vendor\Navdata\Controller\Account;

    use Magento\Customer\Model\Account\Redirect as AccountRedirect;
    use Magento\Customer\Api\Data\AddressInterface;
    use Magento\Framework\Api\DataObjectHelper;
    use Magento\Framework\App\Action\Context;
    use Magento\Customer\Model\Session;
    use Magento\Framework\App\Config\ScopeConfigInterface;
    use Magento\Framework\App\ObjectManager;
    use Magento\Framework\Exception\LocalizedException;
    use Magento\Store\Model\StoreManagerInterface;
    use Magento\Customer\Api\AccountManagementInterface;
    use Magento\Customer\Helper\Address;
    use Magento\Framework\UrlFactory;
    use Magento\Customer\Model\Metadata\FormFactory;
    use Magento\Newsletter\Model\SubscriberFactory;
    use Magento\Customer\Api\Data\RegionInterfaceFactory;
    use Magento\Customer\Api\Data\AddressInterfaceFactory;
    use Magento\Customer\Api\Data\CustomerInterfaceFactory;
    use Magento\Customer\Model\Url as CustomerUrl;
    use Magento\Customer\Model\Registration;
    use Magento\Framework\Escaper;
    use Magento\Customer\Model\CustomerExtractor;
    use Magento\Framework\Exception\StateException;
    use Magento\Framework\Exception\InputException;
    use Magento\Framework\Data\Form\FormKey\Validator;

    /**
     * @SuppressWarnings(PHPMD.TooManyFields)
     * @SuppressWarnings(PHPMD.CouplingBetweenObjects)
     */
    class CreatePost extends \Magento\Customer\Controller\Account\CreatPost
    {

        protected $accountManagement;

        protected $addressHelper;

        protected $formFactory;

        protected $subscriberFactory;

        protected $regionDataFactory;

        protected $addressDataFactory;

        protected $registration;

        protected $customerDataFactory;

        protected $customerUrl;

        protected $escaper;

        protected $customerExtractor;

        protected $urlModel;

        protected $dataObjectHelper;

        protected $session;

        private $accountRedirect;

        private $cookieMetadataFactory;

        private $cookieMetadataManager;

        private $formKeyValidator;

        public function __construct(
            Context $context,
            Session $customerSession,
            ScopeConfigInterface $scopeConfig,
            StoreManagerInterface $storeManager,
            AccountManagementInterface $accountManagement,
            Address $addressHelper,
            UrlFactory $urlFactory,
            FormFactory $formFactory,
            SubscriberFactory $subscriberFactory,
            RegionInterfaceFactory $regionDataFactory,
            AddressInterfaceFactory $addressDataFactory,
            CustomerInterfaceFactory $customerDataFactory,
            CustomerUrl $customerUrl,
            Registration $registration,
            Escaper $escaper,
            CustomerExtractor $customerExtractor,
            DataObjectHelper $dataObjectHelper,
            AccountRedirect $accountRedirect,
            Validator $formKeyValidator = null
        ) {
            $this->session = $customerSession;
            $this->scopeConfig = $scopeConfig;
            $this->storeManager = $storeManager;
            $this->accountManagement = $accountManagement;
            $this->addressHelper = $addressHelper;
            $this->formFactory = $formFactory;
            $this->subscriberFactory = $subscriberFactory;
            $this->regionDataFactory = $regionDataFactory;
            $this->addressDataFactory = $addressDataFactory;
            $this->customerDataFactory = $customerDataFactory;
            $this->customerUrl = $customerUrl;
            $this->registration = $registration;
            $this->escaper = $escaper;
            $this->customerExtractor = $customerExtractor;
            $this->urlModel = $urlFactory->create();
            $this->dataObjectHelper = $dataObjectHelper;
            $this->accountRedirect = $accountRedirect;
            $this->formKeyValidator = $formKeyValidator ?: ObjectManager::getInstance()->get(Validator::class);
            parent::__construct($customerSession,$scopeConfig,$storeManager,$accountManagement,$addressHelper,$formFactory,$subscriberFactory,$regionDataFactory,$addressDataFactory,$customerDataFactory,$customerUrl,$registration,$escaper,$customerExtractor,$dataObjectHelper,$accountRedirect,$context);
        }

        /**
         * Retrieve cookie manager
         *
         * @deprecated 100.1.0
         * @return \Magento\Framework\Stdlib\Cookie\PhpCookieManager
         */
        private function getCookieManager()
        {
            if (!$this->cookieMetadataManager) {
                $this->cookieMetadataManager = ObjectManager::getInstance()->get(
                    \Magento\Framework\Stdlib\Cookie\PhpCookieManager::class
                );
            }
            return $this->cookieMetadataManager;
        }

        /**
         * Retrieve cookie metadata factory
         *
         * @deprecated 100.1.0
         * @return \Magento\Framework\Stdlib\Cookie\CookieMetadataFactory
         */
        private function getCookieMetadataFactory()
        {
            if (!$this->cookieMetadataFactory) {
                $this->cookieMetadataFactory = ObjectManager::getInstance()->get(
                    \Magento\Framework\Stdlib\Cookie\CookieMetadataFactory::class
                );
            }
            return $this->cookieMetadataFactory;
        }

        /**
         * Add address to customer during create account
         *
         * @return AddressInterface|null
         */
        protected function extractAddress()
        {
            if (!$this->getRequest()->getPost('create_address')) {
                return null;
            }

            $addressForm = $this->formFactory->create('customer_address', 'customer_register_address');
            $allowedAttributes = $addressForm->getAllowedAttributes();

            $addressData = [];

            $regionDataObject = $this->regionDataFactory->create();
            foreach ($allowedAttributes as $attribute) {
                $attributeCode = $attribute->getAttributeCode();
                $value = $this->getRequest()->getParam($attributeCode);
                if ($value === null) {
                    continue;
                }
                switch ($attributeCode) {
                    case 'region_id':
                        $regionDataObject->setRegionId($value);
                        break;
                    case 'region':
                        $regionDataObject->setRegion($value);
                        break;
                    default:
                        $addressData[$attributeCode] = $value;
                }
            }
            $addressDataObject = $this->addressDataFactory->create();
            $this->dataObjectHelper->populateWithArray(
                $addressDataObject,
                $addressData,
                \Magento\Customer\Api\Data\AddressInterface::class
            );
            $addressDataObject->setRegion($regionDataObject);

            $addressDataObject->setIsDefaultBilling(
                $this->getRequest()->getParam('default_billing', false)
            )->setIsDefaultShipping(
                $this->getRequest()->getParam('default_shipping', false)
            );
            return $addressDataObject;
        }

        /**
         * Create customer account action
         *
         * @return void
         * @SuppressWarnings(PHPMD.CyclomaticComplexity)
         * @SuppressWarnings(PHPMD.NPathComplexity)
         */
        public function execute()
        {
            /** @var \Magento\Framework\Controller\Result\Redirect $resultRedirect */
            $resultRedirect = $this->resultRedirectFactory->create();
            if ($this->session->isLoggedIn() || !$this->registration->isAllowed()) {
                $resultRedirect->setPath('*/*/');
                return $resultRedirect;
            }

            if (!$this->getRequest()->isPost() || !$this->formKeyValidator->validate($this->getRequest())) {
                $url = $this->urlModel->getUrl('*/*/create', ['_secure' => true]);
                $resultRedirect->setUrl($this->_redirect->error($url));
                return $resultRedirect;
            }

            $this->session->regenerateId();

            try {
                $address = $this->extractAddress();
                $addresses = $address === null ? [] : [$address];

                $customer = $this->customerExtractor->extract('customer_account_create', $this->_request);
                $customer->setAddresses($addresses);

                $password = $this->getRequest()->getParam('password');
                $confirmation = $this->getRequest()->getParam('password_confirmation');
                $redirectUrl = $this->session->getBeforeAuthUrl();

                $this->checkPasswordConfirmation($password, $confirmation);

                $customer = $this->accountManagement
                    ->createAccount($customer, $password, $redirectUrl);

                if ($this->getRequest()->getParam('is_subscribed', false)) {
                    $this->subscriberFactory->create()->subscribeCustomerById($customer->getId());
                }

                $this->_eventManager->dispatch(
                    'customer_register_success',
                    ['account_controller' => $this, 'customer' => $customer]
                );

                $confirmationStatus = $this->accountManagement->getConfirmationStatus($customer->getId());
                if ($confirmationStatus === AccountManagementInterface::ACCOUNT_CONFIRMATION_REQUIRED) {
                    $email = $this->customerUrl->getEmailConfirmationUrl($customer->getEmail());
                    // @codingStandardsIgnoreStart
                    $this->messageManager->addSuccess(
                        __(
                            'You must confirm your account. Please check your email for the confirmation link or <a href="%1">click here</a> for a new link.',
                            $email
                        )
                    );
                    // @codingStandardsIgnoreEnd
                    $url = $this->urlModel->getUrl('*/*/index', ['_secure' => true]);
                    $resultRedirect->setUrl($this->_redirect->success($url));
                } else {
                    $this->session->setCustomerDataAsLoggedIn($customer);
                    $this->messageManager->addSuccess($this->getSuccessMessage());
                    $requestedRedirect = $this->accountRedirect->getRedirectCookie();
                    if (!$this->scopeConfig->getValue('customer/startup/redirect_dashboard') && $requestedRedirect) {
                        $resultRedirect->setUrl($this->_redirect->success($requestedRedirect));
                        $this->accountRedirect->clearRedirectCookie();
                        return $resultRedirect;
                    }
                    $resultRedirect = $this->accountRedirect->getRedirect();
                }
                if ($this->getCookieManager()->getCookie('mage-cache-sessid')) {
                    $metadata = $this->getCookieMetadataFactory()->createCookieMetadata();
                    $metadata->setPath('/');
                    $this->getCookieManager()->deleteCookie('mage-cache-sessid', $metadata);
                }

                return $resultRedirect;
            } catch (StateException $e) {
                $url = $this->urlModel->getUrl('customer/account/forgotpassword');
                // @codingStandardsIgnoreStart
                $message = __(
                    'There is already an account with this email address. If you are sure that it is your email address, <a href="%1">click here</a> to get your password and access your account.',
                    $url
                );
                // @codingStandardsIgnoreEnd
                $this->messageManager->addError($message);
            } catch (InputException $e) {
                $this->messageManager->addError($this->escaper->escapeHtml($e->getMessage()));
                foreach ($e->getErrors() as $error) {
                    $this->messageManager->addError($this->escaper->escapeHtml($error->getMessage()));
                }
            } catch (LocalizedException $e) {
                $this->messageManager->addError($this->escaper->escapeHtml($e->getMessage()));
            } catch (\Exception $e) {
                $this->messageManager->addException($e, __('We can\'t save the customer.'));
            }

            $this->session->setCustomerFormData($this->getRequest()->getPostValue());
            $defaultUrl = $this->urlModel->getUrl('*/*/create', ['_secure' => true]);
            $resultRedirect->setUrl($this->_redirect->error($defaultUrl));
            return $resultRedirect;
        }

        /**
         * Make sure that password and password confirmation matched
         *
         * @param string $password
         * @param string $confirmation
         * @return void
         * @throws InputException
         */
        protected function checkPasswordConfirmation($password, $confirmation)
        {
            if ($password != $confirmation) {
                throw new InputException(__('Please make sure your passwords match.'));
            }
        }

        /**
         * Retrieve success message
         *
         * @return string
         */
        protected function getSuccessMessage()
        {
            if ($this->addressHelper->isVatValidationEnabled()) {
                if ($this->addressHelper->getTaxCalculationAddressType() == Address::TYPE_SHIPPING) {
                    // @codingStandardsIgnoreStart
                    $message = __(
                        'If you are a registered VAT customer, please <a href="%1">click here</a> to enter your shipping address for proper VAT calculation.',
                        $this->urlModel->getUrl('customer/address/edit')
                    );
                    // @codingStandardsIgnoreEnd
                } else {
                    // @codingStandardsIgnoreStart
                    $message = __(
                        'If you are a registered VAT customer, please <a href="%1">click here</a> to enter your billing address for proper VAT calculation.',
                        $this->urlModel->getUrl('customer/address/edit')
                    );
                    // @codingStandardsIgnoreEnd
                }
            } else {
             //   $message = __('Thank you for registering with %1.', $this->storeManager->getStore()->getFrontendName());
                $message = __('Thank you for registering %1.');
            }
            return $message;
        }
    }

etc/di.xml

    <config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../../../../../lib/internal/Magento/Framework/ObjectManager/etc/config.xsd">


     <preference for="Magento\Customer\Controller\Account\CreatPost" type="Vendor\Navdata\Controller\Account\CreatPost" />
    </config> 

Answer 1

If you only need to translate success message Than There no need to override whole controller.

You can create CSV file and add your desired translation.

app/design/frontend/VendorName/ThemeName/i18n/en_US.csv

Than add as below.

"Thank you for registering with %1.","Your custom text"

Deploy static content and clear cache.