js怎么传值给servlet

// 假设要传递两个参数：name 和 age
var name = "张三";
var age = 25;
var url = "YourServletURL?name=" + encodeURIComponent(name) + "&age=" + encodeURIComponent(age);
window.location.href = url; // 跳转到Servlet

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    String name = request.getParameter("name");
    String ageStr = request.getParameter("age");
    int age = Integer.parseInt(ageStr);
    
    // 处理接收到的参数
    System.out.println("Name: " + name + ", Age: " + age);
    
    // 返回响应（可选）
    response.setContentType("text/html");
    PrintWriter out = response.getWriter();
    out.println("<h1>接收到的参数</h1>");
    out.println("<p>Name: " + name + "</p>");
    out.println("<p>Age: " + age + "</p>");
}

<form id="myForm" action="YourServletURL" method="post">
    <input type="text" name="name" value="张三">
    <input type="number" name="age" value="25">
    <button type="submit">提交</button>
</form>

<!-- 或者使用JavaScript提交 -->
<script>
document.getElementById('myForm').submit();
</script>

var data = {
    name: "张三",
    age: 25
};

fetch('YourServletURL', {
    method: 'POST',
    headers: {
        'Content-Type': 'application/json'
    },
    body: JSON.stringify(data)
})
.then(response => response.json())
.then(data => {
    console.log('成功:', data);
})
.catch((error) => {
    console.error('错误:', error);
});

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.15.2</version>
</dependency>

import com.fasterxml.jackson.databind.ObjectMapper;

// ...

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    ObjectMapper mapper = new ObjectMapper();
    MyData data = mapper.readValue(request.getInputStream(), MyData.class);
    
    // 处理接收到的数据
    System.out.println("Name: " + data.getName() + ", Age: " + data.getAge());
    
    // 返回响应
    response.setContentType("application/json");
    mapper.writeValue(response.getOutputStream(), new ResponseMessage("数据接收成功"));
}

// 数据类
class MyData {
    private String name;
    private int age;
    // getters 和 setters
}

// 响应消息类
class ResponseMessage {
    private String message;
    public ResponseMessage(String message) { this.message = message; }
    // getters 和 setters
}