Seven of China’s most popular e-cigarette brands put out statements on social media late Friday saying that they supported the decision by the regulator. RELX, the most popular brand in China with 60 percent market share, said it “firmly supports” the decision by the regulator. “We will fully act to terminate all sales and advertising on the internet,” it said on its social media account.

Two of China’s biggest e-commerce platforms, Alibaba and JD.Com, did not respond to a request for comment.

“Most of the e-cigarette companies are doing the internet model,” said Zhang Jiafeng, 25, an e-cigarette lover who lives in Sichuan and runs social media marketing company that targets vapers and has more than 10 thousand followers.

“They are newly founded and need the internet to promote their product so this notice will be quite a hit on them,” he said. As a consumer, he added, this will mean more regulation and supervision from the government, something that he said would be a positive development.

For the industry, China provided a lucrative opportunity.

At an exposition for e-cigarettes in Shanghai this week, buyers and sellers milled about as 250 companies from all over the world advertised flavored liquids like Bulgarian rose, bubble tea and Moutai, a Chinese liquor. Models walked around in pencil dresses and heels handing out free samples of e-cigarette fluids, near booths from American brands like Twist and local players like the state monopoly, China National Tobacco.

“We want to be here and make our presence here in China,” said Mike Harcarik, a sales manager at Twist. “Look at it here, it’s a huge market.”

While Juul, one of the best known e-cigarettes companies, faces multiple state and federal investigations in the United States, it has targeted the overseas market for e-cigarettes, a strategy its new chief executive, K.C. Crosthwaite, highlighted to employees in an all-hands meeting in September. But that plan has hit roadblocks in Asia, with China’s crackdown and India’s announcement in September that it would ban the sale of e-cigarettes.