add an api example (#204)

dart-archive · Feb 5, 2023 · 0b8025c · 0b8025c
1 parent f118e00
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diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -4,6 +4,7 @@
 - Adopted the `package:dart_flutter_team_lints` linting rules.
 - Fixed an issue with `querySelector` where it would fail in some cases with
   descendant or sibling combinators (#157).
+- Add an API example in `example/`.
 
 ## 0.15.1
 

diff --git a/README.md b/README.md
@@ -9,9 +9,9 @@ A Dart implementation of an HTML5 parser.
 Parsing HTML is easy!
 
 ```dart
-import 'package:html/parser.dart' show parse;
+import 'package:html/parser.dart';
 
-main() {
+void main() {
   var document = parse(
       '<body>Hello world! <a href="www.html5rocks.com">HTML5 rocks!');
   print(document.outerHtml);

diff --git a/example/main.dart b/example/main.dart
@@ -0,0 +1,57 @@
+import 'package:html/dom.dart';
+import 'package:html/dom_parsing.dart';
+import 'package:html/parser.dart';
+
+void main(List<String> args) {
+  var document = parse('''
+<body>
+  <h2>Header 1</h2>
+  <p>Text.</p>
+  <h2>Header 2</h2>
+  More text.
+  <br/>
+</body>''');
+
+  // outerHtml output
+  print('outer html:');
+  print(document.outerHtml);
+
+  print('');
+
+  // visitor output
+  print('html visitor:');
+  _Visitor().visit(document);
+}
+
+// Note: this example visitor doesn't handle things like printing attributes and
+// such.
+class _Visitor extends TreeVisitor {
+  String indent = '';
+
+  @override
+  void visitText(Text node) {
+    if (node.data.trim().isNotEmpty) {
+      print('$indent${node.data.trim()}');
+    }
+  }
+
+  @override
+  void visitElement(Element node) {
+    if (isVoidElement(node.localName)) {
+      print('$indent<${node.localName}/>');
+    } else {
+      print('$indent<${node.localName}>');
+      indent += '  ';
+      visitChildren(node);
+      indent = indent.substring(0, indent.length - 2);
+      print('$indent</${node.localName}>');
+    }
+  }
+
+  @override
+  void visitChildren(Node node) {
+    for (var child in node.nodes) {
+      visit(child);
+    }
+  }
+}