不能使文本框只接受数字作为输入

<input type="number" />

<input type="text" id="numericInput" />

<script>
  var numericInput = document.getElementById("numericInput");
  numericInput.addEventListener("input", function(event) {
    var value = event.target.value;
    event.target.value = value.replace(/\D/g, ""); // 只保留数字字符
  });
</script>

// 前端发送请求的代码
fetch("/validate", {
  method: "POST",
  headers: {
    "Content-Type": "application/json"
  },
  body: JSON.stringify({ value: inputValue })
})
  .then(response => response.json())
  .then(data => {
    if (data.valid) {
      // 输入合法
    } else {
      // 输入非法，显示错误信息
    }
  });

// 后端处理请求的代码
const express = require("express");
const app = express();

app.use(express.json());

app.post("/validate", (req, res) => {
  const value = req.body.value;
  if (/^\d+$/.test(value)) {
    res.json({ valid: true });
  } else {
    res.json({ valid: false, error: "只允许输入数字" });
  }
});

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