Crate quick_xml[−][src]
High performance XML reader/writer.
Description
Reader
: a low level xml pull-reader where buffer allocation/clearing is left to userWriter
: a xml writer. Can be nested with readers if you want to transform xmls
Examples
Reader
use quick_xml::Reader; use quick_xml::events::Event; let xml = r#"<tag1 att1 = "test"> <tag2><!--Test comment-->Test</tag2> <tag2> Test 2 </tag2> </tag1>"#; let mut reader = Reader::from_str(xml); reader.trim_text(true); let mut count = 0; let mut txt = Vec::new(); let mut buf = Vec::new(); // The `Reader` does not implement `Iterator` because it outputs borrowed data (`Cow`s) loop { match reader.read_event(&mut buf) { // for triggering namespaced events, use this instead: // match reader.read_namespaced_event(&mut buf) { Ok(Event::Start(ref e)) => { // for namespaced: // Ok((ref namespace_value, Event::Start(ref e))) match e.name() { b"tag1" => println!("attributes values: {:?}", e.attributes().map(|a| a.unwrap().value) .collect::<Vec<_>>()), b"tag2" => count += 1, _ => (), } }, // unescape and decode the text event using the reader encoding Ok(Event::Text(e)) => txt.push(e.unescape_and_decode(&reader).unwrap()), Ok(Event::Eof) => break, // exits the loop when reaching end of file Err(e) => panic!("Error at position {}: {:?}", reader.buffer_position(), e), _ => (), // There are several other `Event`s we do not consider here } // if we don't keep a borrow elsewhere, we can clear the buffer to keep memory usage low buf.clear(); }
Writer
use quick_xml::Writer; use quick_xml::events::{Event, BytesEnd, BytesStart}; use quick_xml::Reader; use std::io::Cursor; use std::iter; let xml = r#"<this_tag k1="v1" k2="v2"><child>text</child></this_tag>"#; let mut reader = Reader::from_str(xml); reader.trim_text(true); let mut writer = Writer::new(Cursor::new(Vec::new())); let mut buf = Vec::new(); loop { match reader.read_event(&mut buf) { Ok(Event::Start(ref e)) if e.name() == b"this_tag" => { // crates a new element ... alternatively we could reuse `e` by calling // `e.into_owned()` let mut elem = BytesStart::owned(b"my_elem".to_vec(), "my_elem".len()); // collect existing attributes elem.extend_attributes(e.attributes().map(|attr| attr.unwrap())); // copy existing attributes, adds a new my-key="some value" attribute elem.push_attribute(("my-key", "some value")); // writes the event to the writer assert!(writer.write_event(Event::Start(elem)).is_ok()); }, Ok(Event::End(ref e)) if e.name() == b"this_tag" => { assert!(writer.write_event(Event::End(BytesEnd::borrowed(b"my_elem"))).is_ok()); }, Ok(Event::Eof) => break, Ok(e) => assert!(writer.write_event(e).is_ok()), // or using the buffer // Ok(e) => assert!(writer.write(&buf).is_ok()), Err(e) => panic!("Error at position {}: {:?}", reader.buffer_position(), e), } buf.clear(); } let result = writer.into_inner().into_inner(); let expected = r#"<my_elem k1="v1" k2="v2" my-key="some value"><child>text</child></my_elem>"#; assert_eq!(result, expected.as_bytes());
Modules
events |
Defines zero-copy XML events used throughout this library. |
Structs
Reader |
A low level encoding-agnostic XML event reader. |
Writer |
XML writer. |
Enums
Error |
The error type used by this crate. |
Type Definitions
Result |
A specialized |