wwJsonSerializer::Serialize

This class can serialize FoxPro objects, values, collections and cursors to JSON and deserialize JSON strings into FoxPro objects, values or collections. Arrays are supported only as members of objects - all lists should be expressed preferably as Collections.

Here's an example that demonstrates how wwJsonSerializer works when round-tripping data:

lcJson = '{ "id": 50445, "message": "Whooo hooo", ' +;
         '  "status": 10 , "entered": "2018-11-21T23:10:10Z", ' +;
         '  "address": { "street": "123 Timber Ln", "number": 32 } }'

loSer = CREATEOBJECT("wwJsonSerializer")
loResult = loSer.DeserializeJson(lcJson)

? loResult.Id
? loResult.entered

? loSer.Serialize(loResult,.T.)

The serializer supports complex nested structures and can also serialize (but not deserialize) FoxPro tables and cursors by way of a custom string syntax (cursor:AliasName). Objects returned are created dynamically on the fly with all arrays parsed into FoxPro collections.

To serialize:

do wwJsonSerializer
loSer = CREATEOBJECT("wwJsonSerializer")
lcJson = loSer.Serialize(loObject)  && Objects, Values, Collections

To de-serialize:

loObject = loSer.DeserializeJson(lcJson)  && JSON Objects, Values, Arrays 
? loObject.Value

You can also serialize FoxPro Cursors and Tables using the cursor:cursorName syntax:

select * from customers into TCustomers
lcJson = loSer.Serialize("cursor:TCustomers")  && Tables/Cursors

You can cannot directly deserialize cursors, but you can use CollectionToCursor() to turn the returned collection into a cursor.

o.Serialize(lvValue, llFormat)

Return Value

Serialized JSON string

Parameters

lvValue
The value to serialize

llFormat
Pretty formats the JSON output. Alternately you can also use the FormattedOutput=.T.?on the serializer level to achieve the same thing.

Note: formatting re-parses the JSON, so there is some overhead associated with re-formatting the JSON.

Remarks

Json is created as continuous text on a single line. If you would like formatted output pass llFormat as .T.. Note there's some overhead in formatting, as the JSON is generated as continuous text in FoxPro first, then passed back to JSON.NET for formatting which deserializes and reserializes the object.


See also:

Class wwJsonSerialize | wwJsonSerializer::DeserializeJson | wwJsonSerializer::PropertyNameOverrides

© West Wind Technologies, 1996-2023 • Updated: 11/26/22
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