json.indexOf: Difference between revisions

From RPTools Wiki
Jump to navigation Jump to search
(Add indexOf example locating JSON Objects in an array with json.path.read)
mNo edit summary
Line 36: Line 36:
Returns: {{code|-1}}
Returns: {{code|-1}}


'''Finding JSON Objects in an Array.''' You can also find the indexes of a JSON object in an array of JSON objects.<br>
'''Finding JSON Objects in an Array.''' You can also find the indexes of a JSON object in a JSON array.<br>
In this example, [[json.path.read]] gets the object with the unique key {{code|currency}} set to {{code|Gold}} in an array of JSON objects representing money. Note that [[json.get]] is used because json.path.read always returns the object in an array.<br>
In this example, [[json.path.read]] gets the object with the unique key {{code|currency}} set to {{code|Gold}} in an array of JSON objects representing money. Note that [[json.get]] is used because json.path.read always returns the object in an array.<br>
The {{code|currency}} key is presupposed to be unique for every record in this example:
The {{code|currency}} key is presupposed to be unique for every record in this example:

Revision as of 18:05, 17 April 2020

json.indexOf() Function

Introduced in version 1.3b53
Returns the index of the first occurrence of a value in the JSON Array. If the value does not exist in the JSON Array then -1 is returned. All JSON Array indexes start at 0.

Usage

json.indexOf(array, value)
json.indexOf(array, value, start)

Parameters

  • array - The JSON Array to search.
  • value - The value to find the index of in the JSON Array.
  • start - The index to start searching from, if not specified it defaults to 0.

Examples

Find the index of the first occurrence of 1:
[r: json.indexOf("[1,2,3,1,1,3]", 1)]

Returns: 0

Find the index of the first occurrence of 1, starting at index 1:

[r: json.indexOf("[1,2,3,1,1,3]", 1, 1)]

Returns: 3

Find the index of the first occurrence of 2, starting at index 2:

[r: json.indexOf("[1,2,3,1,1,3]", 2, 2)]

Returns: -1

Finding JSON Objects in an Array. You can also find the indexes of a JSON object in a JSON array.
In this example, json.path.read gets the object with the unique key currency set to Gold in an array of JSON objects representing money. Note that json.get is used because json.path.read always returns the object in an array.
The currency key is presupposed to be unique for every record in this example:

[h: moneyJSON = '[
	{"currency":"Copper", "amount":9},
	{"currency":"Silver", "amount":14},
	{"currency":"Gold", "amount":5}
	]']
[h: justGold = json.get(json.path.read(moneyJSON, "[?(@.currency == 'Gold')]"), 0)]
[r: json.indexOf(moneyJSON, justGold)]
Returns: 2

See Also