nfJson

Provides a set of fast performance, reliable and easy to use Json functions using pure VFP.

Project Manager: Marco Plaza

Functions & Usage

( Each function is a single prg - No additional dependencies / Requires VFP9 )

• oJson = nfJsonRead(cJsonString , isFileName,lReviveCollections)

• cJsonString = nfJsonCreate(oVfp, lFormattedOutput, lNoNullArrayItems,cRootName,aMembersFlag)

• nfJsonToCursor(cJson, cCursorName , lForceImportFromArray) ( creates cursor back from Json created using nfCursorToJson4vfp )

• nfCursorToJson4vfp() && converts current open table/cursor to Json suitable for later use of nfJsonToCursor()

• nfCursorToJson(lReturnArray, lArrayofValues, lIncludestruct, lFormattedOutput) __&& converts current open table/cursor to Json

• nfCursorToObject(lCopyToArray, lIncludeStruct)

• BETA PREVIEW: nfOpenJson( cJsonString , [ cArrayPath ], [cCursorStructure & object mappings ] )

  Similar to SqlServer 2016 openJson function. Allows you to convert Json to cursor. Pass jsonString , optional array path using $. as object root and cursor structure as string with following structure for each column: -<fieldName> <castExpression> [<$.propertyPath>] Object types must use JSON as cast type ( see example ). Please check nfOpenJsonTest and https://docs.microsoft.com/en-us/sql/t-sql/functions/openjson-transact-sql for clear understanding.

     text to mssample2 noshow
    [
      {
        "Order": {
          "Number":"SO43659",
          "Date":"2011-05-31T00:00:00"
        },
        "AccountNumber":"AW29825",
        "Item": {
          "Price":2024.9940,
          "Quantity":1
        }
      },
      {
        "Order": {
          "Number":"SO43661",
          "Date":"2011-06-01T00:00:00"
        },
        "AccountNumber":"AW73565",
        "Item": {
          "Price":2024.9940,
          "Quantity":3
        }
      }
    ]
    ENDTEXT
    
    
    nfOpenJson( m.mssample2,'$.array',';
     - Number   v(200) $.Order.Number  ;
     - Date     t      $.Order.Date    ;
     - Customer v(200) $.AccountNumber  ;
     - itemPrice n(6,2) $.Item.Price ;
     - itemQuantity i   $.Item.Quantity ;
     - Order  JSON')
    
    browse
    
    nfOpenJson( m.msSample2 )
    browse
    
    nfOpenJson( m.msSample2,'$.array')
    browse
  

Tests & Sample files

• nfOpenJsonTest: samples taken from https://docs.microsoft.com/en-us/sql/t-sql/functions/openjson-transact-sql

• nfJsonPerfTest.prg: just run it and choose one of the embedded json samples from the list to check performance on your pc. ( Allows you to parse Json from clipboard too. )

• examples.prg will parse the next Json files included in JsonSamples folder. just run from test folder and see sample code and output.

• collectionTest.prg: creates a complex collection , converts it to Json and back to vfp.

• Sample Json files included:

  • youtubesearch.json
  • cycloneForecast.json
  • dropbox.json
  • googleMapsDistance.json
  • iphone photo.json
  • mapquest.json
  • mySimpleArray.json
  • tweeter.json
  • weatherService.json
  • yahooweather.json

Release Notes

2017/08/05

• no matter wich strictdate setting you have set, a JsonDateTime "0000-00-00T00:00:00" will return an empty date.
• valid JsonDates with time "T00:00:00" will return a date value ( ie: {"testDate":"2017-12-01T00:00:00"} )
• invalid dates ( ie 2017/50/50 ) properly formatted as Json Date ( ie: 2017-50-50T00:00:00 ) will throw error; ( previous behavior was to return .null. )

2017/03/10

• fixed: proper support for 19 character strings with ISO basic date format & different strictdate settings.

2017/02/05

• fixed: nfJsonRead bug fix: incorrect parsing for strings terminated with escaped double quotes; minor changes & code refactoring.

2017/01/11

• fixed: nfJsonRead: incorrect unescaped output with "set exact = on"
• escapetest.prg - removed "leftover" lines.

2017/01/11

• fixed issue escaping values terminated with "
• nfJsonRead: removed parameter "isFile" now you can just pass a file name or string
• added test: escapeTest.prg

2016/09/28

• minor bug fix: zero item collections created as 1 empty item collection
• proper indent for raw/formatted collection objects

2016/08/16

• nfJsonPerfTest: added compiled exe, samples file ships as a separate file for you to edit
• fixed bug on test prgs: clean installs would fail due to missing temp folder on distribution zip w/o tests\temp folder
• fixed bug on collectionTest

2016/07/22

• nfJsonRead: Improved error management
• CollectionTest: added new test

2016/07/20

• Fixed bug: missing closing curly brace on collections as object member
• Updated collections program test

2016/07/09

• Automatic cast for datetime properties ( ISO-8601 basic format & vfp compilant as described on https://en.wikipedia.org/wiki/ISO_8601#Times. )
• nfJsonToCursor Bug Fix: "Date/datetime evaluated to an invalid value" while running under "strictdate = 1" converting empty dates back from Json

2016/07/04

• Added support for control characters encoding ( chr( 0) ~ chr(31) )

2016/05/05

• invalid Json error shows calling program information

2016/04/02

• complex nested objects/arrays validation
• missing object/array closures validation

2016/03/28

• nfJsonRead performs JSON validation: invalid Json throws error indicating reason.
• nfJsonPerfTest: proper error management enabled for invalid Json input from clipboard
• nfJsonToCursor: use of strict date format