Bale played 90 minutes for his country in Saturday's 1-1 draw against Finland in Cardiff, the first time he has done so since completing his world-record move to the Bernabeu.
It was the former Tottenham man's 43rd cap for his country and he is set to pass the 50 mark during the upcoming Euro 2016 campaign, where he will be a crucial part of Wales' effort to reach a first major finals since 1958.
Some had predicted Bale's involvement with Wales may be limited by his move to Real, and the Spanish club's desire to protect one of their prized assets.
But Bale has turned up when his country has called this season, notably making an immediate return to Cardiff from his unveiling in Madrid to join the Wales squad for their September fixtures against Macedonia and Serbia.
And, given the 24-year-old's stated pride in pulling on the red shirt, Leicester midfielder King sees no reason why Bale would ever be prepared to limit his involvement or not give 100 per cent for his country.
"Having someone like that in your squad is a massive bonus, he would walk into any team at the moment and there is no question that he will be turning up and putting in a shift," he said.
"That's part and parcel for him and he is a great professional and an outstanding player and the more games he plays for us the better.
"I don't think he would ever not turn up or not try his best.
"He said earlier this week that playing for his country is the biggest honour and he has shown that and he is nearly up to 50 caps, which for someone of his age is an amazing achievement, and long may it continue."
King netted just his second Wales goal against the Finns, heading home from Hal Robson-Kanu's cross.
The 25-year-old got his chance after Aaron Ramsey was ruled out by flu and backed up a good performance in Belgium last month.
Midfield is arguably the most competitive area of the Wales squad with Ramsey, Joe Allen, Joe Ledley, David Vaughan, Jack Collison and Andrew Crofts among those battling for places.
And King was pleased to have taken his opportunity to stake a claim.
"It would have been great to get that result and some momentum, but their late goal has unfortunately denied us that," he said.
"It's been nice to have a run in the team and get a few games and I was really pleased to score, it's just a shame it wasn't the winner.
"Obviously, there is massive competition for places with guys like Aaron and other Premier League players in midfield, but that competition is something I want to thrive on and it was nice to score."