has a film ever been made on this?
Yes, "Camelot".
Film, television, and theatrical adaptations
Alan Jay Lerner and Frederick Loewe's 1960 musical "Camelot" (which was made into a movie in 1967) is based mostly on the last two books of "The Once and Future King" and features White's idea of having Thomas Malory make a cameo appearance at the end, again as "Tom of Warwick".
when did the arthurian legends reach their height of popularity With the outbreak of the Second World War. who was he? He was a legendary British leader who, according to medieval histories and romances, led the defence of Britain against Saxon invaders in the late 5th and early 6th centuries. who was he married to? UNANSWERABLE any novel in which his romance tradition is continuing in 20th century? "The Once and Future King", "Arthur Rex", and "The Mists of Avalon". who was the author of the first one mentioned above? T.H.White. when was it first published? 1958.
Yes, "Camelot" Yes,  The movie adds a more comical side to the original story, including song and dance, as in most Disney films. Yes, Walt Disney produced an adaptation of "The Sword in the Stone".
The Once and Future King The Once and Future King The Once and Future King
Film, television, and theatrical adaptations Film, television, and theatrical adaptations Film, television, and theatrical adaptations
Alan Jay Lerner and Frederick Loewe's 1960 musical "Camelot" (which was made into a movie in 1967) is based mostly on the last two books of "The Once and Future King" and features White's idea of having Thomas Malory make a cameo appearance at the end, again as "Tom of Warwick". Although Walt Disney initially purchased the film rights to "The Ill-Made Knight" in 1944, he eventually produced an adaptation of "The Sword in the Stone" (released in 1963). This movie reflects more the sense of humour of Disney's team of animators than White's. The movie adds a more comical side to the original story, including song and dance, as in most Disney films.
 Although Walt Disney initially purchased the film rights to "The Ill-Made Knight" in 1944, he eventually produced an adaptation of "The Sword in the Stone" (released in 1963). 
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The Once and Future King [SEP] Film, television, and theatrical adaptations
Although Walt Disney initially purchased the film rights to "The Ill-Made Knight" in 1944, he eventually produced an adaptation of "The Sword in the Stone" (released in 1963). This movie reflects more the sense of humour of Disney's team of animators than White's. The movie adds a more comical side to the original story, including song and dance, as in most Disney films. Alan Jay Lerner and Frederick Loewe's 1960 musical "Camelot" (which was made into a movie in 1967) is based mostly on the last two books of "The Once and Future King" and features White's idea of having Thomas Malory make a cameo appearance at the end, again as "Tom of Warwick".