我有一个需要$query = $this->db->query("SELECT value FROM mydb WHERE ID='example'");
// Check if there are any rows returned from the query
if ($query->num_rows > 0) {
// Here you are getting array of your row.
$row = $query->row;
// Now here you are getting specific column value from our row into your variable.
$variable = $row['yourcolumnname'];
// Here we are echo our variable to test it.
echo $variable;
}
的用户模型。我没有在他们的个人资料中询问用户这些，而是采用了更现代的方式，并添加了一个位置自动完成功能。当用户选择自动填充选项时，我将city_id, state_id, and country_id存储在表单上的隐藏字段中。当表格提交时，我想确保这个城市是我城市桌上的有效城市。截至目前，我的用户控制器中有这个逻辑。我做这样的事情：
city_id所以我猜有几个问题（我对Rails很新）：
def update
# I override the strong parameters here so I can add / remove them if I
# need to.
@user_params = user_params
if @user_params[:city_id]
@city = City.find_by id: @user_params[:city_id]
if @city.present?
@user_params[:city_id] = @city.id
@user_params[:state_id] = @city.state.id
@user_params[:country_id] = @city.country.id
else
# Here I'd like to tell the user they submitted an invalid location
# rather than invalid city, state, country. I don't believe
# I can add custom validation errors in the controller though.
end
end
# Update the user, etc.
end
之类的一组验证如何进入一个验证，如：无效的位置。答案 0 :(得分：0)
删除后，您只需要验证城市的存在，而不是city_id - http://railsguides.net/belongs-to-and-presence-validation-rule1/
class User
validates :city, presence: { message: "Location is invalid" }
end