Jansson-Delphi

Jansson-Delphi - a Delphi binding for Jansson library, which is a C library for encoding, decoding and manipulating JSON data.

Jansson-Delphi consists of a Jansson's prebuilt dynamic-link library (DLL) and a PAS file with all required declarations which are required to use Jansson's API.

You can build the DLL on your own by following this manual: https://jansson.readthedocs.io/en/latest/gettingstarted.html#compiling-and-installing-jansson

Original Jansson github project: https://github.com/akheron/jansson

Version

Current version of Jansson-Delphi is 2.13.1, which means that it is based on corresponding version of the Jansson library.

Jansson-Delphi was developed and tested on the following systems:

• Borland Delphi 2006, Win32

It can also be used in newer Delphi versions. To make sure that it works correctly, build and run DUnit tests from the test directory.

Documentation

Original API reference: https://jansson.readthedocs.io/en/latest/apiref.html

Some useful code snippets

The original Jansson header contains following macro definitions for iteration over objects and arrays:

• json_object_foreach(object, key, value)
• json_object_foreach_safe(object, n, key, value)
• json_array_foreach(array, index, value)

You can use these code snippets to replace the macroses:

//#define json_object_foreach(object, key, value) \
//    for(key = json_object_iter_key(json_object_iter(object)); \
//        key && (value = json_object_iter_value(json_object_key_to_iter(key))); \
//        key = json_object_iter_key(json_object_iter_next(object, json_object_key_to_iter(key))))
var
  LKey: PAnsiChar;
  LObject: PJson;
  LValue: PJson;

----------

LKey := json_object_iter_key(json_object_iter(LObject));
while (LKey <> nil) do begin
  LValue := json_object_iter_value(json_object_key_to_iter(LKey));
  if (LValue = nil) then begin
    Break;
  end;

  // Do something here with LKey and LValue.

  LKey := json_object_iter_key(json_object_iter_next(LObject, json_object_key_to_iter(LKey)));
end;

//#define json_object_foreach_safe(object, n, key, value)     \
//    for(key = json_object_iter_key(json_object_iter(object)), \
//            n = json_object_iter_next(object, json_object_key_to_iter(key)); \
//        key && (value = json_object_iter_value(json_object_key_to_iter(key))); \
//        key = json_object_iter_key(n), \
//            n = json_object_iter_next(object, json_object_key_to_iter(key)))
var
  LObject: PJson;
  LKey: PAnsiChar;
  LN: Pointer;
  LValue: PJson;

----------

LKey := json_object_iter_key(json_object_iter(LObject));
LN := json_object_iter_next(LObject, json_object_key_to_iter(LKey));
while (LKey <> nil) do begin
  LValue := json_object_iter_value(json_object_key_to_iter(LKey));
  if (LValue = nil) then begin
    Break;
  end;

  // Do something here with LKey and LValue.

  LKey := json_object_iter_key(LN);
  LN := json_object_iter_next(LObject, json_object_key_to_iter(LKey));
end;

//#define json_array_foreach(array, index, value) \
//	for(index = 0; \
//		index < json_array_size(array) && (value = json_array_get(array, index)); \
//		index++)
var
  LIndex: Integer;
  LValue: PJson;

----------

LIndex := 0;
while LIndex < json_array_size(AArray) do begin
  LValue := json_array_get(AArray, LIndex);
  if (LValue = nil) then begin
    Break;
  end;

  // Do something here with LValue.

  Inc(LIndex);
end;

License

Jansson is released under the MIT license. (LICENSE.C.txt)

Jansson-Delphi is released under the MIT license. (LICENSE.txt)