E-books continued their surge in popularity last year, surpassing hardcover books and paperbacks to become the dominant format for adult fiction in 2011, according to a survey of publishers released Wednesday.

For several years, consumers have been rapidly switching from print to digital for reading novels, a sign of the growing strength of the e-book for narrative, straightforward storytelling.

Over all, digital books kept up their explosive growth in 2011, the survey confirmed. Publishers’ net revenue from sales of e-books more than doubled last year, reaching $2.07 billion, up from $869 million in 2010. E-books accounted for 15.5 percent of publishers’ revenues.

But as digital revenue grew, print sales suffered, dropping to $11.1 billion in 2011 from $12.1 billion in 2010.

The annual survey, known as BookStats, includes data from nearly 2,000 publishers of all sizes. It was conducted by two trade groups, the Book Industry Study Group and the Association of American Publishers.

The survey also revealed that revenue in the overall trade book business was relatively flat. Publishers’ net revenues in 2011 were $13.97 billion, up from $13.9 billion in 2010, an increase of 0.5 percent.

Children’s books, a category that includes young-adult fiction like the hugely popular “Hunger Games” trilogy, grew 12 percent in 2011, to $2.78 billion from $2.48 billion in 2010.

Despite the closing of hundreds of Borders stores, brick-and-mortar stores remained the largest sales channel for books, the survey found. Many in the publishing industry worried that the disappearance of Borders would have a significant effect on the overall business, but analysts said it appeared that many of those customers had moved to other retailers.

Online retailing, however, increased to $5.04 billion in 2011 from $3.72 billion in 2010.

“I would never dare to call an industry healthy, but it certainly seems to be robust,” said Dominique Raccah, the publisher of Sourcebooks and co-chairwoman of the Book Industry Study Group, adding that unit sales of books had increased. “We, as an industry, appear to be getting books into more hands.”