JSON Support

DWScript provides built-in, high-performance JSON support through the JSON object and the JSONVariant type.

Core Methods

Method	Parameters	Description
`Parse`	`jsonStr`	Parses JSON string into a `JSONVariant`.
`Stringify`	`value`	Converts a value (Record, Class, Array, etc) to a JSON string.
`PrettyStringify`	`value [, indent]`	Formats JSON for readability.
`Serialize`	`value`	Converts a native value into a `JSONVariant` object.
`NewObject / NewArray`		Creates a dynamic JSON container.

Serialization Rules

DWScript uses a set of consistent rules for automatic serialization via JSON.Stringify:

Type	Inclusion Rule
Classes	Only published fields and properties are included.
Named Records	Only published fields are included.
Anonymous Records	All fields are automatically included.
Arrays	All elements are included as a JSON array.

Example: Classes

type
  TUser = class
  published
    Name : String;
    Age : Integer;
  private
    InternalId : Integer; // Will be ignored
  end;

var u := new TUser;
u.Name := 'Alice'; u.Age := 30;
PrintLn(JSON.Stringify(u));

Result

{"Age":30,"Name":"Alice"}

Dynamic Access

Using JSONVariant, you can access keys using dot notation or array indexing.

var data := JSON.Parse('{"items": [10, 20]}');
PrintLn(data.items[0]);

Result

JSONVariant Helper Methods

When working with JSONVariant, several helper methods are available. Note that these must be called with parentheses () to avoid conflict with JSON field names.

Method	Returns	Description
`Defined()`	`Boolean`	Returns `True` if the value is not `Undefined`.
`Length()`	`Integer`	Returns the number of elements (Array) or keys (Object).
`Low()`	`Integer`	Returns the lowest index (usually 0).
`High()`	`Integer`	Returns the highest index of an array.
`Add(item)`	`Integer`	Appends an item to a JSON array. Returns the new index.
`Push(item)`	`Integer`	Alias for `Add`.
`Delete(id)`	`(none)`	Removes an item by index (Array) or key name (Object).
`Swap(i, j)`	`(none)`	Swaps two elements in an array.
`Clone()`	`JSONVariant`	Returns a deep copy of the structure.
`ToString()`	`String`	Returns the JSON string representation.
`TypeName()`	`String`	Returns 'Object', 'Array', 'String', 'Number', 'Boolean', 'Null' or 'Undefined'.
`ElementName(i)`	`String`	Returns the key name at the given index (for Objects).
`AsInteger / AsFloat`		Explicit conversion helpers.
`AsString / AsBoolean`		Explicit conversion helpers.

Specialized Parsers

For high-performance scenarios, these static methods on the JSON object parse strings directly into native Pascal arrays, bypassing JSONVariant overhead.

Method	Parameters	Returns
`ParseIntegerArray`	`(jsonStr)`	`array of Integer`
`ParseFloatArray`	`(jsonStr)`	`array of Float`
`ParseStringArray`	`(jsonStr)`	`array of String`

Auto-Serialization

DWScript can automatically stringify complex types like Records and Classes. Simply pass the instance to JSON.Stringify.

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