decode string encoded in utf-8 format in android

问题

I have a string which comes via an xml , and it is text in German. The characters that are German specific are encoded via the UTF-8 format. Before display the string I need to decode it.

I have tried the following:

try {
    BufferedReader in = new BufferedReader(
            new InputStreamReader(
                    new ByteArrayInputStream(nodevalue.getBytes()), "UTF8"));
    event.attributes.put("title", in.readLine());
} catch (UnsupportedEncodingException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
} catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}

I have also tried this:

try {
    event.attributes.put("title", URLDecoder.decode(nodevalue, "UTF-8"));
} catch (UnsupportedEncodingException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}

None of them are working. How do I decode the German string

thank you in advance.

UDPDATE:

@Override
public void characters(char[] ch, int start, int length)
        throws SAXException {
    // TODO Auto-generated method stub
    super.characters(ch, start, length);
    if (nodename != null) {
        String nodevalue = String.copyValueOf(ch, 0, length);
        if (nodename.equals("startdat")) {
            if (event.attributes.get("eventid").equals("187")) {
            }
        }
        if (nodename.equals("startscreen")) {
            imageaddress = nodevalue;
        }
        else {
            if (nodename.equals("title")) {
                // try {
                // BufferedReader in = new BufferedReader(
                // new InputStreamReader(
                // new ByteArrayInputStream(nodevalue.getBytes()), "UTF8"));
                // event.attributes.put("title", in.readLine());
                // } catch (UnsupportedEncodingException e) {
                // // TODO Auto-generated catch block
                // e.printStackTrace();
                // } catch (IOException e) {
                // // TODO Auto-generated catch block
                // e.printStackTrace();
                // }
                // try {
                // event.attributes.put("title",
                // URLDecoder.decode(nodevalue, "UTF-8"));
                // } catch (UnsupportedEncodingException e) {
                // // TODO Auto-generated catch block
                // e.printStackTrace();
                // }
                event.attributes.put("title", StringEscapeUtils
                        .unescapeHtml(new String(ch, start, length).trim()));
            } else
                event.attributes.put(nodename, nodevalue);
        }
    }
}

回答1:

You could use the String constructor with the charset parameter:

try
{
    final String s = new String(nodevalue.getBytes(), "UTF-8");
}
catch (UnsupportedEncodingException e)
{
    Log.e("utf8", "conversion", e);
}

Also, since you get the data from an xml document, and I assume it is encoded UTF-8, probably the problem is in parsing it.

You should use InputStream/InputSource instead of a XMLReader implementation, because it comes with the encoding. So if you're getting this data from a http response, you could either use both InputStream and InputSource

try
{
    HttpEntity entity = response.getEntity();
    final InputStream in = entity.getContent();
    final SAXParser parser = SAXParserFactory.newInstance().newSAXParser();
    final XmlHandler handler = new XmlHandler();
    Reader reader = new InputStreamReader(in, "UTF-8");
    InputSource is = new InputSource(reader);
    is.setEncoding("UTF-8");
    parser.parse(is, handler);
    //TODO: get the data from your handler
}
catch (final Exception e)
{
    Log.e("ParseError", "Error parsing xml", e);
}

or just the InputStream:

try
{
    HttpEntity entity = response.getEntity();
    final InputStream in = entity.getContent();
    final SAXParser parser = SAXParserFactory.newInstance().newSAXParser();
    final XmlHandler handler = new XmlHandler();
    parser.parse(in, handler);
    //TODO: get the data from your handler
}
catch (final Exception e)
{
    Log.e("ParseError", "Error parsing xml", e);
}

Update 1

Here is a sample of a complete request and response handling:

try
{
    final DefaultHttpClient client = new DefaultHttpClient();
    final HttpPost httppost = new HttpPost("http://example.location.com/myxml");
    final HttpResponse response = client.execute(httppost);
    final HttpEntity entity = response.getEntity();

    final InputStream in = entity.getContent();
    final SAXParser parser = SAXParserFactory.newInstance().newSAXParser();
    final XmlHandler handler = new XmlHandler();
    parser.parse(in, handler);
    //TODO: get the data from your handler
}
catch (final Exception e)
{
    Log.e("ParseError", "Error parsing xml", e);
}

Update 2

As the problem is not the encoding but the source xml being escaped to html entities, the best solution is (besides correcting the php to do not escape the response), to use the apache.commons.lang library's very handy static StringEscapeUtils class.

After importing the library, in your xml handler's characters method you put the following:

@Override
public void characters(final char[] ch, final int start, final int length) 
    throws SAXException
{
    // This variable will hold the correct unescaped value
    final String elementValue = StringEscapeUtils.
        unescapeHtml(new String(ch, start, length).trim());
    [...]
}

Update 3

In your last code the problem is with the initialization of the nodevalue variable. It should be:

String nodevalue = StringEscapeUtils.unescapeHtml(
    new String(ch, start, length).trim());

来源：https://stackoverflow.com/questions/5828091/decode-string-encoded-in-utf-8-format-in-android