如何使用Asp.net核心mvc在搜索功能中添加多个选项

我知道简单的搜索结果如下:

<form asp-controller="User" asp-action="search">
      <input type="text" name="search"/>
      <button class="btn btn-primary" id="searchBtn">SÖK</button>
</form>

public class User : Controller
{
    public IActionResult Search(string search = null)
        {
            IEnumerable<User> users;
            if (!string.IsNullOrEmpty(search))
            {
                users = _users.GetAllUsers().Where(s => s.Email.ToLower().Contains(search.ToLower()));

            }
            else
            {
                users = _users.GetAllUsers();
            }
            return View("index", users);
        }
}

但我想做的是添加指定搜索字段的功能,如: 或 按姓名

public IActionResult Search(string search = null, string field = null)
        {
            IEnumerable<User> users;
            if (!string.IsNullOrEmpty(search))
            {
                 if (!string.IsNullOrEmpty(field))
                    {
                        if(field == "ByEmail")
                        {
                           //I'll modify this to not get all rows from the database, but wrote it 
                           //like that for simplicity 
                           users = _users.GetAllUsers().Where(s => s.Email.ToLower().Contains(search.ToLower()));
                        }
                        else if(field =="ByName")
                        {
                           users = _users.GetAllUsers().Where(s => s.Name.ToLower().Contains(search.ToLower()));
                        }

                   }
                   else
                   {
                       users = _users.GetAllUsers();
                   }
            else
            {
                users = _users.GetAllUsers();
            }
            return View("index", users);
        }

非常感谢。