README.md

cJsonPath

cJsonPath.pkg

A DataFlex class which will allow you to get either object handles or values from JSON objects using their path.

Author: Mike Peat Date: 06/02/2020

Usage: To return a JSON object at a path:

   Get JsonAtPath of oJsonPathObject hoSourceJsonObject, path to hoVar
 
 Or:
   
   Move (JsonAtPath(oJsonPathObject, hoSourceJsonObject, path)) to hoVar

To return a value at a path:

   Get ValueAtPath of oJsonPathObject hoSourceJsonObject path to sVar
   
 Or
   
   Move (ValueAtPath(oJsonPathObject, hoSourceJson, path)) to sVar

Path notation:

A string with JSON object names, separated by dots "." and array indices in square brackets: "foo.bar.baz[0].bill[1][0]"

Sample JSON (in object hoJson):

{
	"foo": {
		"bar": {
			"baz": [
				66.123,
				{
					"jim": "jack"
				},
				False,
				{
					"bob": 42
				},
				{
					"kim": "possible"
				},
				[55, 1, 19, {
					"Mork": [
						[35, 67, 88, 100, [21, 33, 45, "Tim"]]
					]
				}]
			]
		}
	}
}

Examples (where the cJsonPath object is called oJPath):

Move (JsonAtPath(oJPath, hoJson, "foo.bar.baz[5][3].Mork[0][4][3]")) to hoObj

Get ValueAtPath of oJPath hJson "foo.bar.baz[5][3].Mork[0][4][3]" to sVal
  (sVal = "Tim")

In the first example the JSON object would be returned; if you then performed Move (JsonValue(hoObj)) to sVal you would get the same result as the second example - i.e. "Tim".

NOTE: JSON is case-sensitive, so your path-strings must exactly match the object names ("foo" is not "Foo") in the JSON file.

Also added the function CountAtPath to return the count of array members.

2022-04-06: Added JsonPath.pkg, which just uses the cJsonPath class, creates an object of that class, then adds three global functions: JsonObjectAtPath, JsonValueAtPath and JsonCountAtPath to call the methods of it. You can just Use JsonPath.pkg then call those global functions.