Skip to content

testmigrator/htmlparserV5

BranchesTags
 
 

Folders and files

NameName
Last commit message
Last commit date

Latest commit

 

History

15 Commits
test
test
 
 
LICENSE
LICENSE
 
 
Makefile
Makefile
 
 
README.md
README.md
 
 
html.cpp
html.cpp
 
 
html.hpp
html.hpp
 
 

Repository files navigation

Usage

Direct access to nodes

html::parser p;
html::node_ptr node = p.parse(R"(<!DOCTYPE html><div attr="val">text</div><!--comment-->)");
// `parse` method returns root node of type html::node_t::none
assert(node->type_node == html::node_t::none);
assert(node->at(0)->type_node == html::node_t::doctype);
assert(node->at(1)->type_node == html::node_t::tag);
assert(node->at(1)->at(0)->type_node == html::node_t::text);
assert(node->at(2)->type_node == html::node_t::comment);
std::cout << "Number of children elements: " << node->size() << std::endl; // 3
std::cout << "DOCTYPE: " << node->at(0)->content << std::endl; // html
std::cout << "Tag name: " << node->at(1)->tag_name << std::endl; // div
std::cout << "Attr value: " << node->at(1)->get_attr("attr") << std::endl; // val
std::cout << "Text node: " << node->at(1)->at(0)->content << std::endl; // text
std::cout << "Comment: " << node->at(2)->content << std::endl; // comment
std::cout << "Print all: " << std::endl << node->to_html() << std::endl;

Access nodes using select method

html::parser p;
html::node_ptr node = p.parse(R"(<div id="my_id"><p class="my_class"></p></div>)");
std::cout << node->select("div#my_id p.my_class")->to_html() << std::endl;

Access nodes using callbacks (called when parsing HTML)

html::parser p;

// Callback with selector to filter elements
p.set_callback("meta[http-equiv='Content-Type'][content*='charset=']", [](html::node& n) {
	if (n.type_node == html::node_t::tag && n.type_tag == html::tag_t::open) {
		std::cout << "Meta charset (with selector): " << n.get_attr("content") << std::endl;
	}
});

// Callback without selector
p.set_callback([](html::node& n) {
	if(n.type_node == html::node_t::tag && n.type_tag == html::tag_t::open && n.tag_name == "meta") {
		if(n.get_attr("http-equiv") == "Content-Type" && n.get_attr("content").find("charset=") != std::string::npos) {
			std::cout << "Meta charset: " << n.get_attr("content") << std::endl;
		}
	}
});

p.parse(R"(<head><title>Title</title><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /></head>)");

Access nodes manually

html::parser p;
html::node_ptr node = p.parse("<ul><li>li1</li><li>li2</li></ul><ol><li>li</li></ol>");

// Search `li` tags which not in `ol`
node->walk([](html::node& n) {
	if(n.type_node == html::node_t::tag && n.tag_name == "ol") {
		return false; // not scan child tags
	}
	if(n.type_node == html::node_t::tag && n.tag_name == "li") {
		std::cout << n.to_html() << std::endl;
	}
	return true; // scan child tags
});

Finding unclosed tags

html::parser p;

// Callback to handle errors
p.set_callback([](html::err_t e, html::node& n) {
	if(e == html::err_t::tag_not_closed) {
		std::string msg;
		html::node* current = &n;
		while(current->get_parent()) {
			msg.insert(0, " " + current->tag_name);
			current = current->get_parent();
		}
		msg.insert(0, "Unclosed tag:");
		std::cout << msg << std::endl;
	}
});

p.parse("<div><p><a></p></div>");

Print document formatted

html::parser p;
html::node_ptr node = p.parse("<ul><li>li1</li><li>li2</li></ul><ol><li>li</li></ol>");

// method takes two arguments, the indentation character and whether to output child elements (tabulation and true by default)
std::cout << node->to_html(' ', true) << std::endl;

Print text content of a node

html::parser p;
html::node_ptr node = p.parse("<div><p><b>First</b> p</p><p><i>Second</i> p</p>Text<br />Text</div>");

// print text with line breaks preserved
std::cout << node->to_text() << std::endl << std::endl;
// print text with line breaks replaced with spaces
std::cout << node->to_text(true) << std::endl;

Building HTML from DOM tree

auto p = html::utils::make_node(html::node_t::tag, "p", {{"id", "p_id"}, {"class", "p_class"}});
p->append(html::utils::make_node(html::node_t::text, "Link:"));
p->append(html::utils::make_node(html::node_t::tag, "br"));
auto a = html::utils::make_node(html::node_t::tag, "a", {{"href", "https://github.com/"}});
p->append(a);
a->append(html::utils::make_node(html::node_t::text, "Github.com"));
std::cout << html::utils::make_node(html::node_t::tag, "div")->append(p)->to_html() << std::endl;

Selectors

Selector example Description select callback
* all elements √ √
div tag name √ √
#id1 id="id1" √ √
.class1 class="class1" √ √
:first first element √ √
:last last element √ -
:eq(3) element index = 3 (starts from 0) √ √
:gt(3) element index > 3 (starts from 0) √ √
:lt(3) element index < 3 (starts from 0) √ √
[attr] element that have attribute "attr" √ √
[attr='val'] attribute is equal to "val" √ √
[attr!='val'] attribute is not equal to "val" or does not exist √ √
[attr^='http:'] attribute starts with "http:" √ √
[attr$='.jpeg'] attribute ends with ".jpeg" √ √
[attr*='/path/'] attribute contains "/path/" √ √
div#id1.class1[attr='val'] element that matches all of these selectors √ √
p,div element that matches any of these selectors √ √
div p i:first nested selectors √ -

About

Fast and lightweight HTML parser

Resources

Readme

License

MIT license
Activity

Stars

0 stars

Watchers

0 watching

Forks

0 forks
Report repository

Releases

No releases published

Packages

 
 
 

Contributors

Languages

  • C++ 97.9%
  • HTML 1.2%
  • Makefile 0.9%