sax解析xml的特殊字符解决方法

1. 如果特殊字符很少，并且出现在特定的tag里，最简单的方法就是生成xml的时候加入标志“<![CDATA[formula]]>”如，

<?xml version='1.0' encoding='UTF-8' standalone='yes' ?><Root><ITEM><AreaID>1</AreaID><ParentID>0</ParentID><AreaName>0</AreaName></ITEM><ITEM><AreaID>2</AreaID><ParentID>1</ParentID><AreaName><![CDATA[aaa<bbb?1:2]]></AreaName></ITEM></Root>

2. 如果不确定哪一个tag会有像<，>等的特殊字符，或者出现特殊字符的tag比较多，则最好使用转义

因为SAX解析判断是否是一个element是通过<>,</>来判断的，所以想大于号、小于号等为了避免混淆，要使用转义

小于号 < &lt;

大于号 > &gt;

与号 & &amp;

单引号 ‘ &apos;

双引号 “ &quot;

比如，

<?xml version='1.0' encoding='UTF-8' standalone='yes' ?><Root><ITEM><AreaID>1</AreaID><ParentID>0</ParentID><AreaName>0</AreaName></ITEM><ITEM><AreaID>2</AreaID><ParentID>1</ParentID><AreaName>a&lt;b</AreaName></ITEM></Root>

<AreaName>a&lt;b</AreaName>

解析的时候，sax解析AreaName的时候进入startElement进入一次，会进入characters至少3次(说至少的意思是有些tag中间会有空格或TAB，本例中只会调用3次)，分别会返回”a“, "<", "b",把这三次拼接起来就是我们需要的字串，完整程序如下

package com.kingman.hello.xml;import org.xml.sax.Attributes;import org.xml.sax.SAXException;import org.xml.sax.helpers.DefaultHandler;import android.util.Log;public class AreaHandler extends DefaultHandler{private static final String TAG = "AreaHandler";    final int AREA_ID = 1;final int PARENT_ID = 2;final int AREA_NAME = 3;AreaFeed mAreaFeed;AreaItem mAreaItem;private int currentstate;private StringBuffer str = null; public AreaHandler() {}@Overridepublic void startDocument() throws SAXException {    Log.v(TAG, "startDocument");mAreaFeed = new AreaFeed();mAreaItem = new AreaItem();}@Overridepublic void endDocument() throws SAXException {    Log.v(TAG, "endDocument");}@Overridepublic void startElement(String uri, String localName, String qName,Attributes attributes) throws SAXException {    Log.v(TAG, "startElement");    str = new StringBuffer();if (localName.equals("ITEM")){mAreaItem = new AreaItem();return;}if (localName.equals("AreaID")){currentstate = AREA_ID;return;}if (localName.equals("ParentID")){currentstate = PARENT_ID;return;}if (localName.equals("AreaName")){currentstate = AREA_NAME;return;}}@Overridepublic void endElement(String uri, String localName, String qName)throws SAXException {    Log.v(TAG, "endElement");    super.endElement(uri, localName, qName);if (localName.equals("ITEM")){mAreaFeed.addItem(mAreaItem);return;}switch (currentstate)        {            case AREA_ID:                mAreaItem.setmAreaID(str.toString());                currentstate = 0;                break;            case PARENT_ID:                mAreaItem.setmParentID(str.toString());                currentstate = 0;                break;            case AREA_NAME:                Log.v(TAG, "AREA_NAME - str = " + str);                mAreaItem.setmAreaName(str.toString());                currentstate = 0;                break;            default:                return;        }}@Overridepublic void characters(char[] ch, int start, int length)throws SAXException {String theString = new String(ch,start,length);str.append(theString);Log.v(TAG, "str = " + str);}public AreaFeed getFeed() {return mAreaFeed;}}

package com.kingman.hello.xml;import java.io.InputStream;import javax.xml.parsers.SAXParser;import javax.xml.parsers.SAXParserFactory;import org.xml.sax.InputSource;import org.xml.sax.XMLReader;import android.app.Activity;import android.os.Bundle;import android.util.Log;import android.widget.ListView;import android.widget.SimpleAdapter;import com.kingman.hello.R;public class SAXParseActivity extends Activity{public final String TAG = "XMLParseActivity";private AreaFeed feed = null;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);this.setContentView(R.layout.xml_listview);feed = getFeed(R.raw.area);showListView();}private AreaFeed getFeed(int r_id) {try    {       InputStream inputStream = null;                      //xml file 放到 assets目录中的       inputStream = getResources().getAssets().open("blog.xml");       //inputStream = openFileInput("blog.xml");                      //创建SAX解析工厂           SAXParserFactory factory = SAXParserFactory.newInstance();           SAXParser parser = factory.newSAXParser();           XMLReader xmlreader = parser.getXMLReader();           //为XMLReader设置内容处理器           AreaHandler xmlHandler = new AreaHandler();           xmlreader.setContentHandler(xmlHandler);//设置事件处理函数           InputSource is = new InputSource(inputStream);           //开始解析文件           xmlreader.parse(is);             return xmlHandler.getFeed();    } catch (Exception ee){    return null;    }}private void showListView()    {Log.v(TAG, "showListView");        ListView itemlist = (ListView) findViewById(R.id.itemlist);        if (feed == null)        {        setTitle("Can't display");        return;        }        SimpleAdapter adapter = new SimpleAdapter(this, feed.getAllItemsForListView(),        R.layout.xml_three_textview, new String[] { AreaItem.AREA_ID, AreaItem.PARENT_ID , AreaItem.AREA_NAME},        new int[] { R.id.tv1 , R.id.tv2, R.id.tv3});        itemlist.setAdapter(adapter);        itemlist.setSelection(0);            }}