Difference between revisions of "IoTGateway/AdvJSON"

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(C functions)
(Fundamental)
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=C++=
 
=C++=
 
==Fundamental==
 
==Fundamental==
 +
* Read only
 +
name = movie[“name”].String();
 +
 +
<font color=red>movie[“name”] = “After Tomorrow”; </font>  <font color=green>//Error, Read only</font>
 +
 +
* Edit
 +
movie.Edit()[“name”] = “After Tomorrow”;                  <font color=green>//Edit 'Value'</font>
 +
 +
movie.Edit()[“name”] << “Name”;                            <font color=green>//Edit 'Key'</font>
 +
 +
<font color=red>movie.Edit()[“Year”] = 2004; </font>        <font color=green>//Error, Can't create new element</font>
 +
* New
 +
movie.New()[“Year”] = 2004; <font color=green>//Create a new element</font>
 +
 +
* Erase
 +
 +
movie[“Year”].Erase();
 +
 +
* Delete
 +
 +
movie[“Year”].Delete();
 +
 
==Erase & Delete==
 
==Erase & Delete==
 
==Operation==
 
==Operation==
 
==Creator==
 
==Creator==
 
==Example==
 
==Example==

Revision as of 03:12, 24 February 2016

What is JSON?

  • JSON stands for JavaScript Object Notation
  • JSON is a lightweight data-interchange format
  • JSON is language independent
  • JSON is "self-describing" and easy to understand

C functions

List

int JSON_Validator(const char *json);

Description

  • This function validates a string in JSON format.

Parameters

  • json [POINTER]
    • a string.

Return Values

  • [0|1] Error or Success.




JSONode *JSON_Parser(const char *json);

Description

  • Translate a string into a tree structure pointer(JSONode);

Parameters

  • json [POINTER]
    • a string.

Return Values

  • (JSONode *)
    • A pointer describes a JSON tree structure.




void JSON_Destory(JSONode **json);

Description

  • Destory a JSON tree sturcture;

Parameters

  • json [POINTER]
    • double-pointer of JSON tree sturcture.

Return Values

  • None




JSONode *JSON_Copy(JSONode *json);

Description

  • Copy a JSON tree sturcture into another pointer.

Parameters

  • json [POINTER]
    • source pointer

Return Values

  • (JSONode *)
    • result pointer




void JSON_Get(JSONode *json, const char *path, char *result, int size);

Description

  • A Structured-Path-Query function.

Parameters

  • json [POINTER]
    • source.
  • path [POINTER]
    • a structure-path string
  • result [POINTER]
    • result string
  • size [NUMBER]
    • the size of result.

Return Values

  • None

Example

char result[256];
JSON_Get(json, "[a][b][c][d]", result, 256);
JSON_Get(json, "/a/b/c/d", result, 256);




void JSON_Cmd(JSONode *json, const char *path, char *assign, int size);

Description

  • A Command-line-like function.

Parameters

  • json [POINTER]
    • source.
  • path [POINTER]
    • a command string
  • assign[POINTER]
    • target
  • size [NUMBER]
    • the size of target.

Return Values

  • None

Example

JSON_Cmd(json, "New [a][b][c][d]", "123", 3);
JSON_Cmd(json, "POST /a/b/c/d", "123", 3);

C++

Fundamental

  • Read only

name = movie[“name”].String();

movie[“name”] = “After Tomorrow”; //Error, Read only

  • Edit

movie.Edit()[“name”] = “After Tomorrow”; //Edit 'Value'

movie.Edit()[“name”] << “Name”; //Edit 'Key'

movie.Edit()[“Year”] = 2004; //Error, Can't create new element

  • New

movie.New()[“Year”] = 2004; //Create a new element

  • Erase

movie[“Year”].Erase();

  • Delete

movie[“Year”].Delete();

Erase & Delete

Operation

Creator

Example