JSONParsedState

Returns 0 if JSON is not parsed, -1 if parsed but invalid, or a positive number representing the JSON type if parsed and valid.

Format 

JSONParsedState ( json )

Parameters 

json - any text expression or field that contains a JSON object or array.

Data type returned 

number

Originated in version 

22.0

Description 

JSONParsedState indicates whether the specified JSON has been parsed (and has a binary representation in memory), and whether the JSON is valid or invalid. This function returns:

  • 0 if the JSON has not been parsed (no binary representation exists in memory).

  • -1 if the JSON was parsed but is invalid. If this JSON is used with the other JSON functions, they return "?" followed by an error message.

  • 1-6 if the JSON is valid and parsed. The value corresponds to one of the JSON types defined in JSONSetElement.

To explicitly parse JSON text, use the JSONParse function.

Example 1 

  1. JSONParse ( "[3]" ) returns [3] because JSONParse returns the input JSON as text if it's valid JSON.

  2. Let ( $a = JSONParse ("[3") ; JSONParsedState ($a) ) returns -1 because $a was set to a parsed but invalid JSON array.

  3. Let ( $a = "[3]" ; JSONParsedState ($a) ) returns 0 because $a wasn't parsed.

  4. JSONParsedState ( JSONParse (Pi) ) returns -1 because the value Pi was parsed but isn't valid JSON.

  5. Let ( $a = JSONSetElement ( "" ; "a" ; "b" ; JSONString ) ; JSONParsedState ($a) ) returns 3 because JSONSetElement created a parsed JSON object stored in $a.

  6. Let ( $a = JSONParse ("[3]") ; JSONParsedState ($a) ) returns 4 because $a was parsed and contains a JSON array.

  7. JSONParsedState ( JSONParse ("") ) returns -1 because an empty string was parsed, which is invalid JSON.

Example 2 

Copy 
Let ( [
  a = "[3";                      /* String is an invalid JSON array */
  b = JSONParse ( a ) ;          /* Error: Input is invalid JSON */
  c = JSONParsedState ( a ) ;    /* 0: 'a' is still only text (not parsed) */
  d = JSONParsedState ( b ) ;    /* -1: 'b' has been parsed but is invalid */
  e = JSONFormatElements ( b ) ; /* Error: 'b' is invalid */
  f = JSONFormatElements ( a )   /* Error: JSON text in 'a' is invalid */
] ;
  a &¶& b &¶& c &¶& d &¶& e &¶& f
)

Returns:

Copy 
[3
? * Line 1, Column 3
  Missing ',' or ']' in array declaration
0
-1
? * Line 1, Column 3
  Missing ',' or ']' in array declaration
? * Line 1, Column 3
  Missing ',' or ']' in array declaration

In contrast, if variable a is a valid JSON array ("[3]"), this example returns:

Copy 
[3]
[3]
0
4
[ 3 ]
[ 3 ]

Note these differences:

  • Line 2:  JSONParse ( a ) returns the original text passed in to JSONParse.

  • Line 4: JSONParsedState ( b ) reflects that variable b has been parsed and is a valid JSON array.

  • Lines 5 and 6: JSONFormatElements returns formatted text for both the parsed JSON in b and the text JSON in a.

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