这段 PHP 代码有什么问题？

Question

我有两个数据库表，一张用于津贴，一张用于扣除。我想计算净工资。

我正在使用 CodeIgniter。这是我当前的代码：

function get_allowances($eid)
{
    $this->db->from('allowances');
    $this->db->where('eid',$eid);
    $query = $this->db->get();

    if($query->num_rows()==1)
    {
        return $query->row();
    }
    else
    {
        //Get empty base parent object, as $item_id is NOT an item
        $salary_obj=new stdClass();

        //Get all the fields from items table
        $fields = $this->db->list_fields('allowances');

        foreach ($fields as $field)
        {
            $salary_obj->$field='';
        }

        return $salary_obj;
    }
}

function get_deductions($eid)
{
    $this->db->from('deductions');
    $this->db->where('eid',$eid);
    $query = $this->db->get();

    if($query->num_rows()==1)
    {
        return $query->row();
    }
    else
    {
        //Get empty base parent object, as $item_id is NOT an item
        $salary_obj=new stdClass();

        //Get all the fields from items table
        $fields = $this->db->list_fields('deductions');

        foreach ($fields as $field)
        {
            $salary_obj->$field='';
        }

        return $salary_obj;
    }
}

在控制器中，

function net_salary($eid)
{
    $allownces[] = $this->Salary->get_allowances($eid);
    $deductions[] = $this->Salary->get_deductions($eid);

    return $net_salary = array_sum($allownces) - array_sum($deductions);
}

我的 net_salary() 函数给出的结果为 0。我做错了什么，如何修复它？

Answer 1

具有复数名称的模型只会返回一个对象。

所以你最终得到的是......

Array
(
    [0] => allowance_object
)

虽然

Array
(
    [0] => deduction_object
)

我们确实需要你的数据库的模式尝试这个（并对扣除进行相同的编辑）......

function get_allowances($eid)
{
    $this->db->from('allowances');
    $this->db->where('eid',$eid);
    $query = $this->db->get();

    if($query->num_rows()==1)
    {
        return $query->row_array();  //<--- return an Array
    }
    else
    {
        // make an array instead of object
        $salary_obj = array();

        //Get all the fields from items table
        $fields = $this->db->list_fields('allowances');

        foreach ($fields as $field)
        {
            $salary_array[$field] = 0;   //<---- add array keys and set to integer 0 instead of empty string.
        }

        return $salary_array;
    }
}

然后在你的 net_salary 函数中

function net_salary($eid)
{
    $allownce = $this->Salary->get_allowances($eid);
    $deduction = $this->Salary->get_deductions($eid);

    return array_sum($allownce) - array_sum($deduction);
}

Answer 2

尝试这样的操作：

function get_values($eid, $table_name)
{
    $this->db->where('eid',$eid);
    $query = $this->db->get($table_name);

    $salary_obj = $query->result();

    $values = array();
    foreach($salary_obj as $row){
        $values[] = $row->value_column_name;
    }

    return $values;
}

其中 value_column_name 是所需值所在的表列的名称（filedname）。

调用控制器：

function net_salary($eid)
{
    $allownces = $this->Salary->get_values($eid, 'allowances');
    $deductions = $this->Salary->get_values($eid, 'deductions');

    return $net_salary = array_sum($allownces) - array_sum($deductions);
}