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Active Forums => Programs => Topic started by: SpriggsySpriggs on July 29, 2020, 09:33:11 am

Title: Parse JSON strings (not an API)
Post by: SpriggsySpriggs on July 29, 2020, 09:33:11 am

As the notice in parentheses in the title states, this is some code for parsing a JSON string and this code is not an API. So far, I've only tested it on JSON responses from my API projects. Those responses have zero whitespace which makes it easy to standardize this function. HOWEVER, other JSON files or strings from other sources might have whitespace and would not work properly with what this is. I'll end up copying all my API projects into one thread and updating their source codes with these functions so they work in a more friendly manner. I had tried to use Galleon's qb_framework and it was a total mess. No documentation that I could find anywhere and so I couldn't even begin to figure out how to translate a JSON to plain text with that. However, I will use it for generating JSON response files at some point because it can do that and it looks like it does it quite well. Anyways, enough rambling. Here is the code for my JSON parsing. I've attached three JSON files from API projects I've worked on so you can test both functions. GetKey will grab the first instance of that key. Useful for a file that has ONE response. GetAllKey will return an array containing all values for that keyname in the JSON file:

Code: QB64: [Select]

1. OPTION _EXPLICIT
2. $CONSOLE:ONLY
3. _DEST _CONSOLE
4.  
5.  
6. DIM JSON AS STRING
7. 'OPEN "nasapod.json" FOR BINARY AS #1
8. 'OPEN "sentimapi.json" FOR BINARY AS #1
9. OPEN "addressvalidation.json" FOR BINARY AS #1
10. JSON = SPACE$(LOF(1))
11. GET #1, , JSON
12.  
13. 'PRINT GetKey("title", JSON) 'for use with nasapod
14. 'PRINT GetKey("url", JSON) 'for use with nasapod
15. 'PRINT GetKey("explanation", JSON) 'for use with nasapod
16. 'REDIM Polarity(0) AS STRING 'for use with sentimapi
17.  
18. PRINT GetKey("delivery_line_1", JSON) 'for use with adddressvalidation
19. PRINT GetKey("last_line", JSON) 'for use with addressvalidation
20. PRINT GetKey("county_name", JSON) 'for use with addressvalidation
21.  
22. 'GetAllKey "polarity", JSON, Polarity() 'for use with sentimapi
23.  
24. 'DIM i
25. 'FOR i = 1 TO UBOUND(Polarity) 'for use with sentimapi
26. '    PRINT Polarity(i)
27. 'NEXT
28.  
29. FUNCTION GetKey$ (keyname AS STRING, JSON AS STRING)
30.     DIM jkey AS STRING
31.     IF INSTR(JSON, CHR$(34) + keyname + CHR$(34)) THEN
32.         jkey = MID$(JSON, INSTR(JSON, CHR$(34) + keyname + CHR$(34)) + LEN(keyname))
33.         jkey = MID$(jkey, INSTR(jkey, ":") + 1)
34.         IF MID$(jkey, 1, 1) = CHR$(34) THEN
35.             jkey = MID$(jkey, 2)
36.         END IF
37.         jkey = MID$(jkey, 1, INSTR(jkey, CHR$(34)) - 1)
38.         IF RIGHT$(jkey, 1) = "," THEN
39.             jkey = MID$(jkey, 1, LEN(jkey) - 1)
40.         END IF
41.     ELSE
42.         GetKey = ""
43.     END IF
44.     GetKey = jkey
45. END FUNCTION
46.  
47. SUB GetAllKey (keyname AS STRING, JSON AS STRING, ParseKey() AS STRING)
48.     DIM jkey AS STRING
49.     DIM x
50.     DO
51.         IF INSTR(JSON, CHR$(34) + keyname + CHR$(34)) THEN
52.             x = x + 1
53.             REDIM _PRESERVE ParseKey(x) AS STRING
54.             JSON = MID$(JSON, INSTR(JSON, CHR$(34) + keyname + CHR$(34)) + LEN(keyname))
55.             jkey = JSON
56.             jkey = MID$(jkey, INSTR(jkey, ":") + 1)
57.             IF MID$(jkey, 1, 1) = CHR$(34) THEN
58.                 jkey = MID$(jkey, 2)
59.             END IF
60.             jkey = MID$(jkey, 1, INSTR(jkey, CHR$(34)) - 1)
61.             IF RIGHT$(jkey, 1) = "," THEN
62.                 jkey = MID$(jkey, 1, LEN(jkey) - 1)
63.             END IF
64.             ParseKey(x) = jkey
65.         END IF
66.     LOOP UNTIL INSTR(JSON, CHR$(34) + keyname + CHR$(34)) = 0
67. END SUB

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