Question

当我到达我的打印语句时，我从以下代码中得到了这个：

This is the for loop value : b
This is the for loop value : b
This is the for loop value : 
This is NOT the for loop value :

我不确定$ le变量是怎么回事，为什么它在for循环中是一回事而在其中是另一回事。

        foreach($this->letdowns AS $ld) 
        {
            $le = "";
            for($i = 0; $i <= sizeof($this->letdowns); $i++)
            {
                $le = $this->letdown_end[$i];
                $msg = "This is the for loop value : " . print_r($le, true) . "<BR>";
                print $msg;
            }
            $msg = "This is NOT the for loop value : " . print_r($le, true) . "<BR>";
            print $msg;

            //$query = "INSERT INTO letdown_events (letdown_line_id, operation_id) "
            $query = "INSERT INTO letdown_events (letdown_line_id, letdown_end, operation_id) "
                    //."values (".$ld->get('id').",".$this->id.")";
                    ."values (".$ld->get('id').",".$le.",".$this->id.")";
            // Make sure this query completes, otherwise rollback the transaction

            var_dump($query);

            if(!$result = mydb::cxn()->query($query)) 
            {
                throw new Exception('An error occurred while trying to create a letdown event for Letdown Line #'.$ld->get('id').': '.mydb::cxn()->error);
            }
        }

当我var_dump变量时，它也是空白的。

string(103) "INSERT INTO letdown_events (letdown_line_id, letdown_end, operation_id) values (1552020000,,1781020000)"

任何人都可以请指出为什么我不能在循环外使用$ le变量，我只是想找到一种使用该查询将其插入数据库的好方法。

Answer 1

for($i = 0; $i < sizeof($this->letdowns); $i++)

不是

for($i = 0; $i <= sizeof($this->letdowns); $i++)

但为什么不简单地使用

foreach($this->letdowns as $le)

可变损失价值

1 个答案: