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为啥这样的二维数组foreach后只有最后一个值输入

时间:2021-07-01 10:21:17 帮助过:1人阅读

为什么这样的二维数组foreach后只有最后一个值输入?
$res = array(
array(
'goods_id' => 14,
'goods_number' => 1
),
array(
'goods_id' => 16,
'goods_number' => 1
),
array(
'goods_id' => 18,
'goods_number' => 1
)
);
上面数组,我想遍历出goods_id 从14 到 18,也就是14,15,16,17,18 ,从而得到goods_id 对应的 goods_number,如果goods_id不存在数组里,goods_number就给予0给它。

foreach($res as $value)
{
if($value['goods_id'] == 14)
{
echo $value['goods_number'];
echo "
";
}
else
{
echo 0;
echo "
";
}

if($value['goods_id'] == 15)
{
echo $value['goods_number'];
}
else
{
echo 0;
echo "
";
}

if($value['goods_id'] == 16)
{
echo $value['goods_number'];
}
else
{
echo 0;
echo "
";
}

if($value['goods_id'] == 17)
{
echo $value['goods_number'];
}
else
{
echo 0;
echo "
";
}

if($value['goods_id'] == 18)
{
echo $value['goods_number'];
}
else
{
echo 0;
echo "
";
}
}
为什么我这样foreach 不行呢?

我要的结果是:
goods_id:14 时 goods_number:1
goods_id:15 时 goods_number:0
goods_id:16 时 goods_number:1
goods_id:17 时 goods_number:0
goods_id:18 时 goods_number:1
所以应该echo的结果是
1
0
1
0
1

为什么我的foreach 得到的不是这样的结果呢?
------解决方案--------------------
$res = array(
array(
'goods_id' => 14,
'goods_number' => 1
),
array(
'goods_id' => 16,
'goods_number' => 1
),
array(
'goods_id' => 18,
'goods_number' => 1
)
);
$newArr = array();
foreach ($res as $key => $value) {
$newArr[$value['goods_id']] = $value['goods_number'];
}

//var_dump(array_values($res));exit;
$range = range(14, 18);

foreach ($range as $keys => $values) {

if(array_key_exists($values, $newArr)){
echo 'goods_id:'.$values.' 时 goods_number:'.$newArr[$values];
echo '
';
}else{

echo 'goods_id:'.$values.' 时 goods_number:0';
echo '
';
}
}

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