使用jQuery创建公共文件时，表单验证不起作用

<script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>

<script src="https://cdn.jsdelivr.net/jquery.validation/1.16.0/jquery.validate.min.js"></script>

$(document).ready(function() {
  $('#myForm').validate({
    rules: {
      username: {
        required: true,
        minlength: 5
      },
      password: {
        required: true,
        minlength: 8
      }
    },
    messages: {
      username: {
        required: "请输入用户名",
        minlength: "用户名至少5个字符"
      },
      password: {
        required: "请输入密码",
        minlength: "密码至少8个字符"
      }
    }
  });
});