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aDataValue

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Inherit from aDataElement

Append​

Adds a value at end of an array and returns the data value to set.

Count​

Returns the number of sub value.

CreateValue​

Creates a data value in the document attachable with SetValue.

Find​

Find(key: CString)

Gets a value from a map at the given key, returns undefined value when not found.
@param key key to map

FindAtPath​

FindAtPath(path: CString)

This method allows to find an element according to a given path. The path has to start with a '/' and can be composed of key and/or index. @param path Path for the element to access to, using / as separator @returns A data value corresponding to the asked node. Undefined on errors

procedure myProcedure
   uses aDataDocument, Doc, aStringFormat
   
   var number : Int4
   var data : aDataDocument
   var myText : Text
   var result : aDataValue
   var error : aDataValue
   
   new(data)
   Write(myText, '{"result": [{"id": 0}, {"id": 1, "count":42}]}}')
   if Doc.JSON.ParseText(data, myText)
      if data.IsDefined
         result = data.FindAtPath('result/1/count')
         Write(result.ToCString)
         ;displays 42
      endIf
   else
      error = data.GetError
      myText := ''
      if Doc.JSON.StringifyText(error, myText)
         Write(myText)
      endIf
   endIf
endProc

Get​

Get(index: Int4)

Gets a value from an array at the given index, returns undefined value when not found.
@param index index to access

GetClassname​

Returns the className meta value of this value.

IsArray​

True when the value is an array, otherwise false.

IsBoolean​

True when the value is a boolean, otherwise false.

IsConstant​

Checks if the value is writable (false) or read only (true).

IsDefined​

True when the value is not undefined, otherwise false.

IsInteger​

True when the value is an integer, otherwise false.

IsMap​

True when the value is a map, otherwise false.

IsNull​

True when the value is null, otherwise false.

IsNumber​

True when the value is a number, otherwise false.

IsString​

True when the value is a string, otherwise false.

IsSymbol​

True when the value is a symbol, otherwise false.

IsUndefined​

True when the value is undefined, otherwise false.

Key​

Returns the key as a CString for a Map node, empty otherwise.

var doc: aDataDocument
var value : aDataValue
var myText: Text

new(doc)
Write(myText, '{"result":true, "count":42}')
if doc.Parse(myText)
  foreach value in doc
    WriteLn(value.Key) ;displays result
  endFor
endIf
dispose(doc)

Map​

Map(key: CString)

Provides a value at the given key, and creates it when not exists.
@param key key to map

NewIterator​

Returns an iterator pointing to the first element in the current node. The current node has to be an Array or a Map. The foreach construct can be used to iterate.

var data: aDataDocument
var value : aDataValue
var myText: Text

new(data)
Write(myText, '{"result":true, "count":42}')
if data.Parse(myText)
  foreach value in data
    WriteLn(value.Key)    ;displays result then count
    WriteLn(value.toCstring)
    WriteLn
  endFor
endIf
myText:=''

Parse​

Parse(json: Text)

Parses a text, constructing the data tree described by the text.
@param json The JSON text to parse
@returns True

var doc: aDataDocument
var myText: Text

new(doc)
Write(myText, '{"result":true, "count":42}')
if doc.Parse(myText)
  if doc.IsDefined
    ;do stuff
  endIf
endIf

Prepend​

Adds a value at begin of an array and returns the data value to set.

SetArray​

Sets the value to an empty array.

SetBool​

SetBool(value: Boolean)

Sets the value to the given boolean.
@param value value to set

SetCString​

SetCString(value: CString)

Sets the value to the given cstring.
@param value value to set

SetCString_​

SetCString_(value: CString)

Deprecated, use SetCString instead
@param value value to set

SetChars​

SetChars(value: tpChar)

Sets the value to the given terminated string.
@param value value to set

SetClassname​

SetClassname(classname: CString)

Setter of the className meta value. @param classname value to assign

SetCopyOf​

SetCopyOf(value: aDataValue)

Fills the value by duplicating the first level of properties or items.
@param value value to set

SetDifferenceOf​

SetDifferenceOf(value: aDataValue, subtrahend: aDataValue)

Fills the value with the difference between minuend and subtrahend.
@param value value to set

SetInt​

SetInt(value: Int8)

Sets the value to the given integer.
@param value value to set

SetMap​

Sets the value to an empty map.

SetNull​

Sets the value to null.

SetNum​

SetNum(value: Num8)

Sets the value to the given number.
@param value value to set

SetText​

SetText(value: Text)

Sets the value to the given text.
@param value: value to set
value is copied and can/should be cleared afterwards.

SetUndefined​

Sets the value to undefined.

SetValue​

SetValue(value: aDataValue)

Fills the value with the content of another.
@param value: value to set

Stringify​

Converts the current node to a string.
@param _Result the output from the conversion

ToBool​

Converts a value a boolean, returns false by default.

ToCString​

Converts a value a cstring, returns '' by default.

ToInt​

Converts a value a integer, returns 0 by default.

ToNum​

Converts a value a number, returns 0.0 by default.

ToText​

Converts a value a text, returns '' by default.