xml_serializable

Description:

xml serializable

XML Serializable #

Provides build builders for handling XML.
The builders generate code when they find members annotated with classes defined in xml_annotation.
Getting Started #

Define the XML document that you would like to serialize.
<?xml version="1.0"?>
<bookshelf>
<book>
<title lang="English">XML Pocket Reference</title>
<author>Simon St. Laurent</author>
<author>Michael James Fitzgerald</author>
<price></price>
</book>
<book>
<title lang="English">HTML and XHTML Pocket Reference</title>
<author>Jennifer Niederst Robbins</author>
<price></price>
</book>
</bookshelf>
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Add the necessary classes to model the XML document.
class Book {
Title? title;

List<String>? authors;

String? price;

Book({
this.title,
this.authors,
this.price,
});
}

class Bookshelf {
List<Book>? books;

String? price;

Bookshelf({
this.books,
this.price,
});
}

enum Language {
mandarin,
spanish,
english,
hindi,
bengali,
}

class Title {
Language? language;

String? text;

Title({
this.language,
this.text,
});
}
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Annotate the classes and properties with XML annotations.
@annotation.XmlRootElement(name: 'book')
@annotation.XmlSerializable()
class Book {
@annotation.XmlElement(name: 'title')
Title? title;

@annotation.XmlElement(name: 'author')
List<String>? authors;

@annotation.XmlElement(name: 'price', isSelfClosing: false)
String? price;

Book({
this.title,
this.authors,
this.price,
});
}

@annotation.XmlRootElement(name: 'bookshelf')
@annotation.XmlSerializable()
class Bookshelf {
@annotation.XmlElement(name: 'book')
List<Book>? books;

@annotation.XmlElement(name: 'price', includeIfNull: false)
String? price;

Bookshelf({
this.books,
this.price,
});
}

@annotation.XmlEnum(fieldRename: annotation.FieldRename.pascal)
enum Language {
mandarin,
spanish,
english,
hindi,
bengali,
}

@annotation.XmlRootElement(name: 'title')
@annotation.XmlSerializable()
class Title {
@annotation.XmlAttribute(name: 'lang')
Language? language;

@annotation.XmlText()
String? text;

Title({
this.language,
this.text,
});
}
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Add the required serialization helper methods to the classes.
@annotation.XmlRootElement(name: 'book')
@annotation.XmlSerializable()
class Book {
@annotation.XmlElement(name: 'title')
Title? title;

@annotation.XmlElement(name: 'author')
List<String>? authors;

@annotation.XmlElement(name: 'price', isSelfClosing: false)
String? price;

Book({
this.title,
this.authors,
this.price,
});

factory Book.fromXmlElement(XmlElement element) =>
_$BookFromXmlElement(element);

@override
String toString() {
return 'Book{title: $title, authors: $authors, price: $price}';
}

void buildXmlChildren(
XmlBuilder builder, {
Map<String, String> namespaces = const {},
}) =>
_$BookBuildXmlChildren(
this,
builder,
namespaces: namespaces,
);

void buildXmlElement(
XmlBuilder builder, {
Map<String, String> namespaces = const {},
}) =>
_$BookBuildXmlElement(
this,
builder,
namespaces: namespaces,
);

List<XmlAttribute> toXmlAttributes({
Map<String, String?> namespaces = const {},
}) =>
_$BookToXmlAttributes(
this,
namespaces: namespaces,
);

List<XmlNode> toXmlChildren({
Map<String, String?> namespaces = const {},
}) =>
_$BookToXmlChildren(
this,
namespaces: namespaces,
);

XmlElement toXmlElement({
Map<String, String?> namespaces = const {},
}) =>
_$BookToXmlElement(
this,
namespaces: namespaces,
);
}

@annotation.XmlRootElement(name: 'bookshelf')
@annotation.XmlSerializable()
class Bookshelf {
@annotation.XmlElement(name: 'book')
List<Book>? books;

@annotation.XmlElement(name: 'price', includeIfNull: false)
String? price;

Bookshelf({
this.books,
this.price,
});

factory Bookshelf.fromXmlElement(XmlElement element) =>
_$BookshelfFromXmlElement(element);

@override
String toString() {
return 'Bookshelf{books: $books, price: $price}';
}

void buildXmlChildren(
XmlBuilder builder, {
Map<String, String> namespaces = const {},
}) =>
_$BookshelfBuildXmlChildren(
this,
builder,
namespaces: namespaces,
);

void buildXmlElement(
XmlBuilder builder, {
Map<String, String> namespaces = const {},
}) =>
_$BookshelfBuildXmlElement(
this,
builder,
namespaces: namespaces,
);

List<XmlAttribute> toXmlAttributes({
Map<String, String?> namespaces = const {},
}) =>
_$BookshelfToXmlAttributes(
this,
namespaces: namespaces,
);

List<XmlNode> toXmlChildren({
Map<String, String?> namespaces = const {},
}) =>
_$BookshelfToXmlChildren(
this,
namespaces: namespaces,
);

XmlElement toXmlElement({
Map<String, String?> namespaces = const {},
}) =>
_$BookshelfToXmlElement(
this,
namespaces: namespaces,
);
}

@annotation.XmlEnum(fieldRename: annotation.FieldRename.pascal)
enum Language {
mandarin,
spanish,
english,
hindi,
bengali,
}

@annotation.XmlRootElement(name: 'title')
@annotation.XmlSerializable()
class Title {
@annotation.XmlAttribute(name: 'lang')
Language? language;

@annotation.XmlText()
String? text;

Title({
this.language,
this.text,
});

factory Title.fromXmlElement(XmlElement element) =>
_$TitleFromXmlElement(element);

@override
String toString() {
return 'Title{language: $language, text: $text}';
}

void buildXmlChildren(
XmlBuilder builder, {
Map<String, String> namespaces = const {},
}) =>
_$TitleBuildXmlChildren(
this,
builder,
namespaces: namespaces,
);

void buildXmlElement(
XmlBuilder builder, {
Map<String, String> namespaces = const {},
}) =>
_$TitleBuildXmlElement(
this,
builder,
namespaces: namespaces,
);

List<XmlAttribute> toXmlAttributes({
Map<String, String?> namespaces = const {},
}) =>
_$TitleToXmlAttributes(
this,
namespaces: namespaces,
);

List<XmlNode> toXmlChildren({
Map<String, String?> namespaces = const {},
}) =>
_$TitleToXmlChildren(
this,
namespaces: namespaces,
);

XmlElement toXmlElement({
Map<String, String?> namespaces = const {},
}) =>
_$TitleToXmlElement(
this,
namespaces: namespaces,
);
}
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Add a part directive to the file that contains the classes.
part 'example.g.dart';
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Add the required package dependencies to your project.
dart pub add xml xml_annotation dev:build_runner dev:xml_serializable
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Run the build runner to generate the serializer code.
dart run build_runner build
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Verify that the generated serializer output is as expected.
// GENERATED CODE - DO NOT MODIFY BY HAND

part of 'example.dart';

// **************************************************************************
// XmlEnumGenerator
// **************************************************************************

const $LanguageEnumMap = {
Language.mandarin: 'Mandarin',
Language.spanish: 'Spanish',
Language.english: 'English',
Language.hindi: 'Hindi',
Language.bengali: 'Bengali'
};

// **************************************************************************
// XmlSerializableGenerator
// **************************************************************************

void _$BookBuildXmlChildren(Book instance, XmlBuilder builder,
{Map<String, String> namespaces = const {}}) {
final title = instance.title;
final titleSerialized = title;
builder.element('title', nest: () {
if (titleSerialized != null) {
titleSerialized.buildXmlChildren(builder, namespaces: namespaces);
}
});
final authors = instance.authors;
final authorsSerialized = authors;
if (authorsSerialized != null) {
for (final value in authorsSerialized) {
builder.element('author', nest: () {
builder.text(value);
});
}
}
final price = instance.price;
final priceSerialized = price;
builder.element('price', isSelfClosing: false, nest: () {
if (priceSerialized != null) {
builder.text(priceSerialized);
}
});
}

void _$BookBuildXmlElement(Book instance, XmlBuilder builder,
{Map<String, String> namespaces = const {}}) {
builder.element('book', namespaces: namespaces, nest: () {
instance.buildXmlChildren(builder, namespaces: namespaces);
});
}

Book _$BookFromXmlElement(XmlElement element) {
final title = element.getElement('title');
final authors = element
.getElements('author')
?.map((e) => e.getText())
.whereType<String>();
final price = element.getElement('price')?.getText();
return Book(
title: title != null ? Title.fromXmlElement(title) : null,
authors: authors?.toList(),
price: price);
}

List<XmlAttribute> _$BookToXmlAttributes(Book instance,
{Map<String, String?> namespaces = const {}}) {
final attributes = <XmlAttribute>[];
return attributes;
}

List<XmlNode> _$BookToXmlChildren(Book instance,
{Map<String, String?> namespaces = const {}}) {
final children = <XmlNode>[];
final title = instance.title;
final titleSerialized = title;
final titleConstructed = XmlElement(
XmlName('title'),
titleSerialized?.toXmlAttributes(namespaces: namespaces) ?? [],
titleSerialized?.toXmlChildren(namespaces: namespaces) ?? []);
children.add(titleConstructed);
final authors = instance.authors;
final authorsSerialized = authors;
final authorsConstructed = authorsSerialized
?.map((e) => XmlElement(XmlName('author'), [], [XmlText(e)]));
if (authorsConstructed != null) {
children.addAll(authorsConstructed);
}
final price = instance.price;
final priceSerialized = price;
final priceConstructed = XmlElement(XmlName('price'), [],
priceSerialized != null ? [XmlText(priceSerialized)] : [], false);
children.add(priceConstructed);
return children;
}

XmlElement _$BookToXmlElement(Book instance,
{Map<String, String?> namespaces = const {}}) {
return XmlElement(
XmlName('book'),
[
...namespaces.toXmlAttributes(),
...instance.toXmlAttributes(namespaces: namespaces)
],
instance.toXmlChildren(namespaces: namespaces));
}

void _$BookshelfBuildXmlChildren(Bookshelf instance, XmlBuilder builder,
{Map<String, String> namespaces = const {}}) {
final books = instance.books;
final booksSerialized = books;
if (booksSerialized != null) {
for (final value in booksSerialized) {
builder.element('book', nest: () {
value.buildXmlChildren(builder, namespaces: namespaces);
});
}
}
final price = instance.price;
final priceSerialized = price;
if (priceSerialized != null) {
builder.element('price', nest: () {
builder.text(priceSerialized);
});
}
}

void _$BookshelfBuildXmlElement(Bookshelf instance, XmlBuilder builder,
{Map<String, String> namespaces = const {}}) {
builder.element('bookshelf', namespaces: namespaces, nest: () {
instance.buildXmlChildren(builder, namespaces: namespaces);
});
}

Bookshelf _$BookshelfFromXmlElement(XmlElement element) {
final books = element.getElements('book');
final price = element.getElement('price')?.getText();
return Bookshelf(
books: books?.map((e) => Book.fromXmlElement(e)).toList(), price: price);
}

List<XmlAttribute> _$BookshelfToXmlAttributes(Bookshelf instance,
{Map<String, String?> namespaces = const {}}) {
final attributes = <XmlAttribute>[];
return attributes;
}

List<XmlNode> _$BookshelfToXmlChildren(Bookshelf instance,
{Map<String, String?> namespaces = const {}}) {
final children = <XmlNode>[];
final books = instance.books;
final booksSerialized = books;
final booksConstructed = booksSerialized?.map((e) => XmlElement(
XmlName('book'),
e.toXmlAttributes(namespaces: namespaces),
e.toXmlChildren(namespaces: namespaces)));
if (booksConstructed != null) {
children.addAll(booksConstructed);
}
final price = instance.price;
final priceSerialized = price;
final priceConstructed = priceSerialized != null
? XmlElement(XmlName('price'), [], [XmlText(priceSerialized)])
: null;
if (priceConstructed != null) {
children.add(priceConstructed);
}
return children;
}

XmlElement _$BookshelfToXmlElement(Bookshelf instance,
{Map<String, String?> namespaces = const {}}) {
return XmlElement(
XmlName('bookshelf'),
[
...namespaces.toXmlAttributes(),
...instance.toXmlAttributes(namespaces: namespaces)
],
instance.toXmlChildren(namespaces: namespaces));
}

void _$TitleBuildXmlChildren(Title instance, XmlBuilder builder,
{Map<String, String> namespaces = const {}}) {
final language = instance.language;
final languageSerialized =
language != null ? $LanguageEnumMap[language]! : null;
if (languageSerialized != null) {
builder.attribute('lang', languageSerialized);
}
final text = instance.text;
final textSerialized = text;
if (textSerialized != null) {
builder.text(textSerialized);
}
}

void _$TitleBuildXmlElement(Title instance, XmlBuilder builder,
{Map<String, String> namespaces = const {}}) {
builder.element('title', namespaces: namespaces, nest: () {
instance.buildXmlChildren(builder, namespaces: namespaces);
});
}

Title _$TitleFromXmlElement(XmlElement element) {
final language = element.getAttribute('lang');
final text = element.getText();
return Title(
language: language != null
? $LanguageEnumMap.entries
.singleWhere(
(languageEnumMapEntry) =>
languageEnumMapEntry.value == language,
orElse: () => throw ArgumentError(
'`$language` is not one of the supported values: ${$LanguageEnumMap.values.join(', ')}'))
.key
: null,
text: text);
}

List<XmlAttribute> _$TitleToXmlAttributes(Title instance,
{Map<String, String?> namespaces = const {}}) {
final attributes = <XmlAttribute>[];
final language = instance.language;
final languageSerialized =
language != null ? $LanguageEnumMap[language]! : null;
final languageConstructed = languageSerialized != null
? XmlAttribute(XmlName('lang'), languageSerialized)
: null;
if (languageConstructed != null) {
attributes.add(languageConstructed);
}
return attributes;
}

List<XmlNode> _$TitleToXmlChildren(Title instance,
{Map<String, String?> namespaces = const {}}) {
final children = <XmlNode>[];
final text = instance.text;
final textSerialized = text;
final textConstructed =
textSerialized != null ? XmlText(textSerialized) : null;
if (textConstructed != null) {
children.add(textConstructed);
}
return children;
}

XmlElement _$TitleToXmlElement(Title instance,
{Map<String, String?> namespaces = const {}}) {
return XmlElement(
XmlName('title'),
[
...namespaces.toXmlAttributes(),
...instance.toXmlAttributes(namespaces: namespaces)
],
instance.toXmlChildren(namespaces: namespaces));
}
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