使用ajax将变量或数组从javaScript发送到节点js

var xhr = new XMLHttpRequest();

xhr.open("POST", "/endpoint", true);

xhr.setRequestHeader("Content-Type", "application/json");

var data = {
  variable: "value",
  array: [1, 2, 3]
};

xhr.send(JSON.stringify(data));

const express = require("express");
const app = express();

app.use(express.json());

app.post("/endpoint", (req, res) => {
  // 处理接收到的数据
  var receivedData = req.body;
  
  // 进行相应的处理逻辑
  
  // 返回响应
  res.send("Data received successfully");
});

app.listen(3000, () => {
  console.log("Server started on port 3000");
});