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HomeBackend DevelopmentPHP TutorialPHP 关于比较两个数组的问题值判断输出的问题

从两个表中取出两组数据,分别存入 $malls 和 $mall_tems

现在需要遍历比较两个数组,如果记录的 color_id 和 size_id 相同,就取出 $mall 的 price 值存入 $malls_tem 的 price 字段中

现在使用以下 foreach 循环,但是不成功,麻烦各位帮忙看看哪里不对。

foreach($mall_tems as $mall_tem){    // 使用的 Laravel,$current_mall 就代表获取当前循环的数据吧。    $current_mall = find($mall_tem->id);     foreach($malls as $mall)    {        if($mall_tem->color_id == $mall->color_id && $mall_tem->size_id == $mall->size_id)         {            $current_mall->price = $mall->price;        }else{            $current_mall->price = '129.00';        }    }}

现在的问题是 $malls 不能正常遍历,$mall_tems price数据可以写入,但是不正确。

谢谢。


回复讨论(解决方案)

除了 $current_mall 含义不明外,并无什么问题

除了 $current_mall 含义不明外,并无什么问题



获取当前循环的商品记录,方便存入 if 判断输出的 price 到这条记录中。后边还有个 $current_mall->save();省略了,

单独分段打印测试时也正常。循环写入时就乱了,有多个符合条件的记录,但是,只有第一条可以正常的写入 if  判断出的价格,其它的定入的都是 else 价格。

你的 $current_mall 是单个对象,并且总是在内层循环里赋值
由于你省略代码时把关键点省略了:$current_mall->save() 在哪里执行的
所以不能明确的说什么

按一般的做法,既然不匹配时 也是要赋值的,就可理解为 $current_mall 是有初值的

    $current_mall->price = '129.00';    foreach($malls as $mall)    {        if($mall_tem->color_id == $mall->color_id && $mall_tem->size_id == $mall->size_id)         {            $current_mall->price = $mall->price;            break; //匹配到就结束        }    }    $current_mall->save();

你的 $current_mall 是单个对象,并且总是在内层循环里赋值
由于你省略代码时把关键点省略了:$current_mall->save() 在哪里执行的
所以不能明确的说什么

按一般的做法,既然不匹配时 也是要赋值的,就可理解为 $current_mall 是有初值的

    $current_mall->price = '129.00';    foreach($malls as $mall)    {        if($mall_tem->color_id == $mall->color_id && $mall_tem->size_id == $mall->size_id)         {            $current_mall->price = $mall->price;            break; //匹配到就结束        }    }    $current_mall->save();




加上break;可以了,原来把数据又覆盖了!
多谢大侠救命之恩。
再次感谢!
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