11.Android-Xml读写

void setOutput(OutputStream os, String encoding);
//设置要写入的XML的文件位置,以及encoding编码格式
//比如:
 //File file = new File(Environment.getExternalStorageDirectory(), "text.xml"); //xmlSerializer.setOutput(new fileOutputStream(file), "utf-8");


void startDocument(String encoding, Boolean standalone);
//设置文档开头描述,比如:" <?xml version="1.0" encoding="utf-8" standalone="yes"?>"
// standalone:表示该XML是否是独立的,默认为true,如果填为false,则表示该XML被外部文件DTD约束

startTag(String namespace, String name);
//写入开始元素标签

endTag(String namespace, String name);
//写入结束元素标签

attribute(String namespace, String name, String value);
//往元素标签里写属性(name="value"),比如<name id="123">

text(String text);
//往元素里添加内容,比如: <name id="123">张三</name>

private void writePersonXml(){
        
        
        XmlSerializer serializer = Xml.newSerializer();
        
        try {
            serializer.setOutput(openFileOutput("persons.xml", MODE_PRIVATE), "utf-8");
            serializer.startDocument("utf-8", true);
            
            serializer.startTag(null,"persons");
            
            //创建两个成员
            serializer.startTag(null,"person");
            serializer.attribute(null, "id", "1");    //添加编号
            
            serializer.startTag(null,"姓名");
            serializer.text("张三");
            serializer.endTag(null,"姓名");
            
            serializer.startTag(null,"age");
            serializer.text("17");
            serializer.endTag(null,"age");
            
            serializer.endTag(null,"person");
            
            serializer.startTag(null,"person");
            serializer.attribute(null, "id", "2"); //添加编号
            
            serializer.startTag(null,"姓名");
            serializer.text("李四");
            serializer.endTag(null,"姓名");
            
            serializer.startTag(null,"age");
            serializer.text("19");
            serializer.endTag(null,"age");
            
            serializer.endTag(null,"person");
            
            serializer.endTag(null,"persons");
            serializer.endDocument();            //结束文档,并将内容写入文件
            
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        
 }

void setInput(InputStream inputStream, String inputEncoding);
//设置要解析的文件以及编码

int getEventType();
//获取当前事件类型,返回的类型有START_DOCUMENT(文档开头)、START_TAG (元素开头)、END_TAG(元素结束)、TEXT (内容)、 END_DOCUMENT(文档结束)

int next();
//获取下个事件类型. 返回的类型和getEventType()一样.

getName();             //获取当前元素名

getTextCharacters();  //获取当前内容(当getEventType ()==TEXT时通过这个来获取元素内容)

nextText();       //获取下个内容(当getEventType ()==START_TAG时通过这个来获取元素内容)

   private void parsePersonsXml(){
        
        XmlPullParser pullParser = Xml.newPullParser();
        
        try {
            pullParser.setInput(this.openFileInput("persons.xml"), "utf-8");
            String name = null;
            String age = null;
            String id = null;
            
            int eventType = pullParser.getEventType();
            
            while(eventType!=pullParser.END_DOCUMENT)
            {
                switch (eventType) {
                case XmlPullParser.START_TAG:
                    
                    if("person".equals( pullParser.getName())){
                        
                        id =  pullParser.getAttributeValue(null, "id");       //获取编号,并初始化内容
                        name =null;
                        age = null;
                        
                    }else if("姓名".equals(pullParser.getName())){
                        
                        name =  pullParser.nextText();    //获取姓名
                        
                    }else if("age".equals(pullParser.getName())){
                        
                        age =  pullParser.nextText();    //获取年龄
                        
                    }
                    break;
                    
                case XmlPullParser.END_TAG:
                    
                    if("person".equals( pullParser.getName())){        
                        
                        System.out.println("person : id="+id+" 姓名="+name+" 年龄="+age); //打印信息
                        
                    }
                    
                    break;
                }
                
                eventType = pullParser.next();        
            }
            
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } 
        
 }