This time I will show you how ajax can add, delete, modify, and check xml files. What are the precautions for adding, deleting, modifying, and checking xml files with ajax? The following is a practical case. Let's take a look. 1.xml file:
<?xml version="1.0" encoding="UTF-8"?><Students> <student id="2"> <name>ttt</name> <age>44</age> </student> <student id="3"> <name>linda2</name> <age>22</age> </student> <student id="4"> <name>linda3</name> <age>23</age> </student> <student id="5"> <name>jack</name> <age>2</age> </student> <student id="1"> <name>yyh1</name> <age>22</age> </student> </Students>
2.Java code
import java.io.File;
import java.io.IOException;
import java.util.Scanner;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.TransformerFactoryConfigurationError;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.w3c.dom.Text;
import org.xml.sax.SAXException;
//在学生管理系统里面，学生的学号是唯一的，姓名有可能重复
public class StudentManager {
public static void main(String[] args) {
try {
Document doc = Domutils.getDoc(new File("xml文件的相对路径"));
Scanner input = new Scanner(System.in);
System.out.println("欢迎来到学生管理系统\n\n\n请输入你要进行什么操作是：\n1.添加学生信息\n2.删除学生信息\n3.修改学生信息\n(请输入前边的序号)");
int num = input.nextInt();
if(num == 1) {
addStudent(doc);
}else if(num == 2) {
delStudent(doc);
}else if(num == 3) {
updStudent(doc);
}
} catch (SAXException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (ParserConfigurationException e) {
e.printStackTrace();
}
}
//修改学生信息
private static void updStudent(Document doc) {
Element updStudent = null;
Scanner input = new Scanner(System.in);
System.out.println("请输入你要修改的学生的学号：");
String studentid = input.nextLine();
System.out.println("请输入新学生的姓名：");
String newName = input.nextLine();
System.out.println("请输入新学生的年龄：");
String newAge = input.nextLine();
//将每一个学生的列出来，for循环判断你要修改信息的学生是哪一个
NodeList list = doc.getElementsByTagName("student");
for(int i = 0; i <list.getLength(); i++) {
if(studentid.equals(list.item(i).getAttributes().getNamedItem("id").getNodeValue())){
updStudent = (Element) doc.getElementsByTagName("student").item(i).getFirstChild().getParentNode();
//对学生的name属性进行赋新值
updStudent.getElementsByTagName("name").item(i).getFirstChild().setNodeValue(newName);
//对学生的age 属性赋新值
updStudent.getElementsByTagName("age").item(i).getFirstChild().setNodeValue(newAge);
}else{
break;
}
}
//找出根元素，将修改后的元素持久化到文件
Element root = doc.getDocumentElement();
transform(root);
System.out.println(updStudent);
}
//删除学生信息
private static void delStudent(Document doc) {
Scanner input = new Scanner(System.in);
//输入你要删除的学生的 学号
System.out.println("请输入要删除学生的学号：");
String studentid = input.nextLine();
Element root = doc.getDocumentElement();
//将学生列成一个表，进行遍历，找对应学号的学生进行删除
NodeList list = doc.getElementsByTagName("student");
for(int i = 0; i < list.getLength(); i++) {
if((studentid).equals(list.item(i).getAttributes().getNamedItem("id").getNodeValue())){
Element delStudent = (Element) doc.getElementsByTagName("student").item(i).getFirstChild().getParentNode();
root.removeChild(delStudent);
break;
}else {
System.out.println("没有该学生");
break;
}
}
//持久化到文件
transform(root);
}
//添加学生信息
private static void addStudent(Document doc) {
// System.out.println(doc.getElementsByTagName("student").item(1).getAttributes().getNamedItem("id").getNodeValue());
Element root = doc.getDocumentElement();
//从控制台输入
Scanner input = new Scanner(System.in);
System.out.println("请输入学生的序号：id = ");
//将学生放到一个列表里面，看我们要添加的学生的学号里面是否已经有了，如果有，需要将新加入的学生的学号改一下
NodeList list = doc.getElementsByTagName("student");
String studentid = input.nextLine();
for(int i = 0; i < list.getLength(); i++) {
if(studentid.equals(list.item(i).getAttributes().getNamedItem("id").getNodeValue())){
System.out.println("该序号学生表里面已经存在，请重新输入一个新的序号：");
studentid = input.nextLine();
}else {
break;
}
}
System.out.println("请输入要添加学生的姓名：name = ");
String name_value = input.nextLine();
System.out.println("请输入要添加学生的年龄：age = ");
String age_value = input.nextLine();
//创建节点
Element student = doc.createElement("student");
Element name = doc.createElement("name");
Element age = doc.createElement("age");
Text namText = doc.createTextNode(name_value);
Text ageText = doc.createTextNode(age_value);
//关联节点之间的关系
root.appendChild(student);
student.appendChild(name);
student.appendChild(age);
student.setAttribute("id", studentid);
name.appendChild(namText);
age.appendChild(ageText);
//持久化到文件
transform(root);
}
//持久化到文件的方法
private static void transform(Element root)
throws TransformerFactoryConfigurationError {
TransformerFactory factory = TransformerFactory.newInstance();
try {
Transformer tf = factory.newTransformer();
tf.transform(new DOMSource(root), new StreamResult(new File("src/com/briup/dom/student.xml")));
} catch (TransformerConfigurationException e) {
e.printStackTrace();
} catch (TransformerException e) {
e.printStackTrace();
}
}
}2.Dom parsing file (encapsulate the part that gets the parsed file)
import java.io.File;
import java.io.IOException;
import java.nio.file.attribute.AclEntry.Builder;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.w3c.dom.Document;
import org.xml.sax.SAXException;
public class Domutils {
public static Document getDoc(File file) throws SAXException, IOException, ParserConfigurationException {
//获取工厂模式
DocumentBuilderFactory factory =
DocumentBuilderFactory.newInstance();
//获取builder对象
DocumentBuilder builder = factory.newDocumentBuilder();
//将要解析文件加载成一个树状文件，开始解析
Document document = builder.parse(file);
return document;
}
}I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!
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Ajax restful interface method of transmitting Json dataHow Ajax+Struts2 implements user input verification Code verification functionThe above is the detailed content of How to add, delete, modify and check xml files with ajax. For more information, please follow other related articles on the PHP Chinese website!
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