For those taking part in the Washington social whirl leading up to the annual White House Correspondents’ Association dinner, it is helpful to know a few basic facts: There will be ample canapés and cocktails, and the occasional broken glass, at the parties before the big night; there will be plenty of television anchors, reporters and talking heads holding forth on current events; and, inevitably, you will run into Bill Nye, the science guy.

Mr. Nye, a Georgetown resident and affable advocate for all things scientific, was a fixture at the festivities in advance of Saturday’s dinner, which has been buffeted by a series of norm-breaking changes.

First came the unsurprising news that the Trump administration, including the president himself, had no intention of participating in the event. Then an appearance by the scheduled host, the comedian Amber Ruffin, was canceled after the association said it wanted to focus not on “the politics of division,” but on celebrating journalism — which is nice, but sounds like a lot less laughs.

But something funny happened on the way to the dinner being a bore: Not only did the parties continue in Washington, but they proliferated into a morning-to-midnight array of breakfasts, brunches and boozy bashes.

Tammy Haddad, a media consultant who helped host two events, noted there were more parties this year, adding that “politics have taken over media” as new outlets have gained on more established publications.

“There’s all these opportunities for regular people, people that have a political opinion, to elevate themselves,” Ms. Haddad said. “So that’s why they’re here.”

Actual celebrities were hard to find, a marked change from last year, when Colin Jost, of “Saturday Night Live,” headlined the dinner and took part in the festivities with his wife, Scarlett Johansson. The closest brush with stop-in-the-street fame came on Friday, when Jason Isaacs, a cast member of “The White Lotus,” arrived at a party hosted by United Talent Agency.

Mr. Isaacs said he was in Washington as part of a group of actors lobbying for the continued funding of the National Endowment for the Arts. “No one quite knows what their fate is going to be,” he said.

It was a line that might have applied to “The White Lotus” — or the Washington press corps, which has been at odds with the White House during President Trump’s first hundred days in office.

Bill de Blasio, the former mayor of New York City, struck a hopeful note for his fellow Democrats during a gala hosted by Semafor, a three-year-old media start-up, at the Smithsonian American Art Museum and National Portrait Gallery.

“I think this actually is going to be another one of those milestone moments, these next few days, of people getting their mojo back,” Mr. de Blasio said.

He was standing with his girlfriend, Nomiki Konst, an activist and political commentator. “I think people are looking for alliances,” she said.

With a guest list of 1,000 people, the Semafor event was pegged to its World Economy Summit, a gathering of business leaders. The party was also dappled with CNN anchors like Wolf Blitzer and Dana Bash. And Mr. Nye, who was snapping selfies with fans.

Ben Smith, Semafor’s editor in chief, described the bewilderment of many attendees in a much-changed Washington. “This is mostly just full of people who are scanning the room for someone who can tell them what is going on,” he said.

Mr. Nye, wearing the Presidential Medal of Freedom awarded to him by President Joseph R. Biden Jr., decried the possibility of NASA budget cuts. “It’s an extraordinary time to be living,” he said.

Like movie stars, administration officials were in short supply, though the White House press secretary, Karoline Leavitt, participated in an interview at an event sponsored by Axios. Ms. Leavitt defended the administration’s handling of the news media and criticized the board of the White House Correspondents’ Association, saying that it “should not dictate who gets to go into the Oval Office and who gets to ride on Air Force One.”

At a Friday happy hour hosted by Crooked Media at Café Riggs, a tourist wearing a MAGA cap signed by the president stumbled to the front door, before turning back. Inside, the “Pod Save America” crew sipped cocktails and considered their past lives writing presidential remarks for the annual dinner.

Jon Lovett, a former speechwriter for President Barack Obama, said that part of the weekend was “not letting Trump define us as being embittered or divided or sour or imperious or meanspirited or scoldy.”

“We have to be joyful and fun and entertaining and unafraid,” he said.

At a Thursday night party at Fish Shop, a soon-to-open restaurant, another young media company, Status, drew a crowd of reporters. Oliver Darcy, one of its founders, said that no Trump officials had been invited. “We want to have people here who like the First Amendment,” he said.

As the guests munched on crab puffs and fried oysters, Erik Wemple, the media critic for The Washington Post, called the room full of reporters — drinks in hand — “a target-rich environment.”

“People come and gossip,” Mr. Wemple said, calling the scene “extremely clubby” and adding, “If you’re a media critic and you don’t make an effort to come out to a couple of these events, you are really not doing your job.”

Another Thursday gathering — at Vital Voices, which encourages female leadership — honored the International Women’s Media Foundation, which supports female journalists. In a top-floor aerie, Jen Psaki, the MSNBC host and former Biden press secretary, lamented Mr. Trump’s decision not to participate in the dinner.

“I think it’s important to show you can take a joke,” she said. “And honor people making fun of you, and people who have criticized you.”

At an event on Friday at the City Tavern, Roger Lynch, the chief executive of Condé Nast, which sponsored the party with Creative Artists Agency, noticed a headline on his phone concerning an effort by Attorney General Pam Bondi to strip away press protections. (Mr. Nye was in attendance here, too.)

Mr. Lynch was asked whether it was a good time to be partying.

“It’s absolutely the right time,” he said. “Because I think it’s really important that our journalists who cover D.C. feel supported and protected.”

At the U.T.A. party, a late-night affair at Osteria Mozza, a cavernous Italian restaurant in Georgetown, attendees of many other parties assembled all over again, challenging the chitchat skills of even those paid to talk.

The CNN host Jake Tapper described an “unsettled and unsettling time in journalism,” noting the resignation of Bill Owens, the executive producer of “60 Minutes,” over disputes regarding journalistic independence.

“I’m not really sure what there is to celebrate,” Mr. Tapper said.

Mr. Isaacs arrived with a fellow actor, Michael Chiklis. A few elected officials trickled in, including Senator Amy Klobuchar, a Democrat, who noted that most politicians aren’t always happy with the way they are covered.

“But you still have to report,” she said. “And you have to respect the rights of the press to report.”

Naturally, Mr. Nye was there, too.