Versions Compared

Old Version 4

changes.mady.by.user Kevin Fournier

Saved on

compared with

New Version 5

changes.mady.by.user Kevin Fournier

Saved on

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...

SRP_JsonX is a special routine whose parameters are interpreted according to the current state. The comment comments above help explain how SRP_JsonX makes its decisions. As you can see, 

...

Code Block
languagebp
titleExample 2
SRP_JsonX_BeginString('MyDocument', '{', JsonxPretty$)
    SRP_JsonX('employees', '[')
        SRP_JsonX('{')
            SRP_JsonX('firstname', 'John')  ; // Since we're in an object, the first parameter is a member name and the second is its value
            SRP_JsonX('lastname', 'Doe')
            SRP_JsonX('age', 21)
        SRP_JsonX('}')
        SRP_JsonX('{')
            SRP_JsonX('firstname', 'Anna')
            SRP_JsonX('lastname', 'Smith')
            SRP_JsonX('age', 32)
        SRP_JsonX('}')
        SRP_JsonX('{"firstname":"Peter", "lastname":"Jones", "age":43}')
    SRP_JsonX(']')
    SRP_JsonX('count', 4)
    SRP_JsonX('active', 1, 'Bool')
    SRP_JsonX('alwaysnull')
    SRP_JsonX('alwaysstring', 4.321, 'String')
Json = SRP_JsonX_End()

The above example Example 2 makes the exact same json as Example 1, but this time we started with SRP_JsonX_BeginString. Note how the calls to SRP_JsonX don't behave any differently. The only difference is that behind the scenes, SRP JsonX is producing pretty json text directly. If you know you are making a json string and that you can plan to build it from the top down, then SRP_JsonX_BeginString will be faster.

...

Code Block
languagejs
{
    "employees": [
        {
            "firstname": "John",
            "lastname": "Doe",
            "age": 21
        },
        {
            "firstname": "Anna",
            "lastname": "Smith",
            "age": 32
        },
        {
            "firstname": "Peter",
            "lastname": "Jones",
            "age": 43
        },
    ],
	"nums": [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
    "alwaysbool": true,
    "alwaysnull": null,
    "alwaysstring": "4.321"
}

Now lets parse it and learn how to navigate it, extract values, and even modify it.

Code Block
languagebp
titleExample 3
$insert SRPJSONX

// Create a new document by parsing the json text
SRP_JsonX_Parse('MyParsedDoc', Json)
	
	// Get the first employee's last name using SRP JsonX path syntax
	LastName = SRP_JsonX_Get('employees[1].lastname')
	
	// If our path points to an object or an array, we'll get the entire object or array as json text
	Employee = SRP_JsonX_Get('employees[1]')
	
	// Routines the get information don't change the current path. If we want to change the
	// current path, we use the Go routines. Let's make the second employee the current path.
	SRP_JsonX_Go('employees[2]')
	
	// Now, if I want to the last name, I must use a path relative to the current one
	LastName = SRP_JsonX_Get('lastname')
	
	// If I try to use a full path, I'll get a null value because all paths are relative to the current one
	LastName = SRP_JsonX_Get('employees[3].lastname')
	
	// We can go back up the json heirarchy one level at a time. This call makes the current path 'employees'
	SRP_JsonX_GoBack()
	
	// Now I can get the third employee's last name
	LastName = SRP_JsonX_Get('[3].lastname')
	
	// We can get make the root the current path at any time
	SRP_JsonX_GoRoot()
	
	// When a value is null or not found, '' is returned by default. If you want a different value,
	// then set the DefaultIfNull parameter to your desired default
	Value = SRP_JsonX_Get('alwaysnull', 'This is null!!!')
	
	// We can also query the json for information (remember, we are currently at the root)
	NumEmployees = SRP_JsonX_Count('employees')
	MemberExists = SRP_JsonX_Has('employees[2].age')
	MemberNames  = SRP_JsonX_Members('employees[3]')
	Type         = SRP_JsonX_Type('alwaysbool')
	Numbers      = SRP_JsonX_Value('nums', ',')
	
	// We can also modify the json
	SRP_JsonX_Clear('nums')
	SRP_JsonX_Delete('employees[2]')
	SRP_JsonX_Sort()
	
// All done with our parsed document.
SRP_JsonX_End()

...

Debugging
Given that SRP JsonX relies so heavily on state, it's important to give you the tools you need to troubleshoot issues. If you want to view the current state of SRP JsonX, call the SRP_JsonX_State or SRP_JsonX_Trace. Both of these show routines give you the current stack and the current paths for each document on the stack. The difference between the two is that SRP_JsonX_Trace displays a message box whereas SRP_JsonX_State returns the stack as an @FM delimited array suitable for viewing in the debugger.
When an SRP JsonX method fails, you can call SRP_JsonX_Error immediately afterwards to get the a detailed error message.
Reference
Here are links to all the SRP JsonX functions.
RoutineDescription
SRP_JsonXAdds json elements to the current document based on the current path.
SRP_JsonX_BeginCreates a new json document.
SRP_JsonX_BeginStringCreates a new json document that must be built in order.
SRP_JsonX_ClearDeletes all elements in an object or array.
SRP_JsonX_CountGets the number of elements in an object or array.
SRP_JsonX_DeleteDeletes an element and all it's children.
SRP_JsonX_EndEnds the current document, optionally returning json.
SRP_JsonX_ErrorGets the last known error.
SRP_JsonX_GetGets an elements value or json.
SRP_JsonX_GoMakes an object or array the current path.
SRP_JsonX_GoBackMakes the parent of the current path the new current path.
SRP_JsonX_GoRootMakes the document root the current path.
SRP_JsonX_HasDetermines if an element exists.
SRP_JsonX_MembersGets all an object's member names.
SRP_JsonX_ParseOpens Parses json into a new json document.
SRP_JsonX_SetSets a value or json.
SRP_JsonX_SortSorts an object's members by member name.
SRP_JsonX_State
Gets the state of the stack and all its documents.
SRP_JsonX_TraceShows the state of the stack and all its documents.
SRP_JsonX_TypeGets an element's type.
SRP_JsonX_ValueGets all an object's or array's values.
...