elementui 表单验证正整数，验证方法

参考：https://blog.csdn.net/sonichenn/article/details/124552540

var validatorPositiveInteger = (rule, value, callback) => {
  if (Number.isInteger(Number(value)) && Number(value) > 0) {
    callback();
  } else {
    callback(new Error("请输入正整数"));
  }
};

      rules: {
        planCode: [{ required: true, message: "计划编号不能为空" }],
        quantity: [
          {
            validator: validatorPositiveInteger,
          },
        ]
}