“Orange you glad I didn’t say banana?” (knock-knock joke)

“Orange you glad I didn’t say banana?” is the punchline of a famously bad “knock-knock” joke. The joke has been recorded since at least 1960.
 
   
Wikipedia: Knock-knock joke
The knock-knock joke is a type of joke, in the format of “call and response”, where the response contains a pun.
     
6 August 1936, The News and Courier (Charleston, SC), “Did You Happen to See—?,” pg. 12, col. 7:
A young lady serving bananas to her husband for breakfast yesterday morning and telling him “Knock knock” to which he answered “Who’s there?” and she kept saying, “Banana” and he kept asking, “Banana who?” the reply being “Banana town” and the husband not catching the point.—(Did you?)
 
Google Books
Western Folklore
1963
Pg. 98:
Banana. Banana who? (Repeat series to this point three times.)
Orange. Orange who?
Orange you glad I didn’t say banana again? (HS 21: C 1: 1960)
 
Google News Archive
23 October 1967, St. Petersburg, (FL) Independent, “Who’s News,” pg. 19-A, col. 1:
When the tangerines ripe in the back yard, Paul and Harry come home from school, take off their shoes and climb up in the tangerine tree where they sit on twisted-limb seats, eat tangerines, tell jokes and talk philosophy. The jokes are pretty bad. Knock-knock. Who’s there? Banana. Banana who? Knock-knock. Who’s there? Banana. Banana who? Knock-knock. Who’s there? Orange. Orange who? Orange you glad I didn’t say banana again?
 
23 July 1972, Sunday Herald Traveler and Sunday Advertiser (Boston, MA), Young Folks Page, col. 7:
Knock knock. Who’s there? Banana. Banana who? Knock knock. Who’s there? Banana. Banana who?? Knock knock. WHo’s there? Orange. Orange who? Orange you glad I didn’t say banana again!
From CINDY ANTHONY.
 
14 October 1972, Newport (RI) Daily News, “Mini Jokes,” Mini Page, pg. 3, col. 1:
John: Knock, Knock.
Jane: Who’s there?
John: Banana.
Jane: Banana who?
John: Knock, Knock.
Jane: Who’s there?
John: Banana.
Jane: Banana who?
John: Knock, knock.
Jane: Who’s there?
John: Orange.
Jane: Orange who?
John: Orange you glad I didn’t say banana?
By Terrie Glenn, Middletown
 
YouTube
Jimmy Valmer Orange you glad I didn’t say Banana
Paul Lennon
Uploaded on Nov 23, 2010
The funniest Jimmy Vulmer stutter ever! “Orange you glad i didn’t say Banana”
 
Twitter
Hot Bearded Fuck
‏@SluttyLumbrjack
Welcome to old joke club, orange you glad I didn’t say banana?
5:56 PM - 8 Nov 2015