如何在codeigniter中插入查询后获取最后一个插入ID

Question

I'm having problem with my controller, I return the the last id I've inserted in the model

public function insert_cropsci($question_data) {    
    $this->db->insert('cropscience_bank', $question_data);
    $questionid =$this->db->insert_id();
    return $questionid;
}

but don't know how to get the id(id only) in my controller

My Controller:

switch ($subject) {
    case 1:
        $this->load->model('insertquestion_model');
        $this->insertquestion_model->insert_cropsci($question_data);
        //I don't know what to do here to get the id(id only)
    break;
}

need some help.

Answer 1

You have to assign value in variable after assigning you will able to use it.

switch ($subject) {
            case 1:
                $this->load->model('insertquestion_model');
                $id = $this->insertquestion_model->insert_cropsci($question_data);
                echo $id;
                break;