我试图检查数组元素是否已经存在，如果不存在，我需要创建一个数组元素，只填充一个值，第二个值设置为null。增加的复杂性是，在检查数组时，我需要忽略第二级，而不必再次循环遍历数组，因为它可能是一个相当大的数组。
我的数组如下：
Array
(
[2016-05-28] => Array
(
[0] => Array
(
[store] => 1
[price] => 12
)
[1] => Array
(
[store] => 7
[price] => 18
)
[2] => Array
(
[store] => 9
[price] =>
)
)
)
我试图检查是否有一个存储值为x的现有元素，如果它不存在，我会创建一个新元素，如果它确实存在，我就会忽略它并继续前进。
在这个例子中，我对$day和$store变量进行了硬编码，但这通常会在For循环中填充，然后在For循环内运行下面的代码段。
我的代码：
$day = '2016-05-28';
$store = 8;
if (!$history[$day][][$store]) {
$history[$day][] = array(
"store" => $store
, "price" => null
);
}
问题是检查元素是否存在if (!$history[$day][][$store]) {，是否可以忽略$day元素和$store元素之间的第二级，以便检查store元素是否存在，我可以使用通配符还是in_array可以工作？
这是我目前正在使用的全部代码。
$setPriceHistoryData = $daoObj->getSetPriceHistoryData($set['id']);
$chartDays = date('Y-m-d', strtotime('-30 days'));
$priceHistoryData = array();
$endDay = date('Y-m-d');
while ($chartDays <= $endDay) {
for ($i = 0; $i < count($setPriceData["price_history_store_data"]); $i++) {
for ($j = 0; $j < count($setPriceHistoryData); $j++) {
if ($setPriceData["price_history_store_data"][$i]["id"] == $setPriceHistoryData[$j]["vph_store"]
&& $chartDays == $setPriceHistoryData[$j]["vph_date"]) {
$priceHistoryData[$chartDays][] = array(
"store" => $setPriceHistoryData[$j]["vph_store"]
, "price" => $setPriceHistoryData[$j]["vph_price"]
);
} else {
if (!$priceHistoryData[$chartDays][]["store"]) {
$priceHistoryData[$chartDays][] = array(
"store" => $setPriceHistoryData[$j]["vph_store"]
, "price" => null
);
}
}
}
}
// Increment day
$chartDays = date('Y-m-d', strtotime("+1 day", strtotime($chartDays)));
}
我会循环浏览所有日期。每天，循环浏览您希望找到的所有门店编号。使用array_filter查找所需的存储。如果你找不到所需的商店，请添加它。
$required_stores = [1,2,3,4]; // stores you wish to add if missing
$source = [
'2016-06-15'=>[
['store'=>1,'price'=>10],['store'=>2,'price'=>10],
],
'2016-06-16'=>[
['store'=>1,'price'=>10],['store'=>3,'price'=>10],
],
'2016-06-17'=>[
['store'=>3,'price'=>10],['store'=>4,'price'=>10],
],
];
//go through all dates. Notice we pass $stores as reference
//using "&" This allows us to modify it in the forEach
foreach ($source as $date => &$stores):
foreach($required_stores as $lookfor):
//$lookfor is the store number we want to add if it's missing
//will hold the store we look for, or be empty if it's not there
$found_store = array_filter(
$stores,
function($v) use ($lookfor){return $v['store']===$lookfor;}
);
//add the store to $stores if it was not found by array_filter
if(empty($found_store)) $stores[] = ['store'=>$lookfor,'price'=>null];
endforeach;
endforeach;
// here, $source is padded with all required stores
正如Rizier123所建议的，您可以使用array_column((。您可以编写一个简单的函数，接受存储编号、引用的历史数组和日期：
$history = [
'2016-05-28' => [
['store' => 1, 'price' => 23],
['store' => 2, 'price' => 23],
['store' => 3, 'price' => 23]
]
];
$store = 8;
$day = '2016-05-28';
function storeHistory($store, &$history, $day)
{
if ( ! isset($history[$day])) {
return false;
}
$presentStores = array_column($history[$day], 'store');
if ( ! in_array($store, $presentStores)) {
$history[$day][] = ['store' => $store, 'price' => null];
}
}
storeHistory($store, $history, $day);
var_dump($history);
array (size=1)
'2016-05-28' =>
array (size=4)
0 =>
array (size=2)
'store' => int 1
'price' => int 23
1 =>
array (size=2)
'store' => int 2
'price' => int 23
2 =>
array (size=2)
'store' => int 3
'price' => int 23
3 =>
array (size=2)
'store' => int 8
'price' => null
应该用几个嵌套循环来完成，我认为如果历史中也不存在日期元素，您可能需要创建一个新的日期元素。
代码注释：
<?php
$history = Array
(
'2016-05-28' => Array
(
0 => Array
(
'store' => 1,
'price' => 12
),
1 => Array
(
'store' => 7,
'price' => 18
),
2 => Array
(
'store' => 9,
'price' => null
)
)
);
print_r($history);
$day = '2016-05-28';
$store = 8;
// loop through dates
foreach ($history as $key=>&$date){
// scan for date
$found_date = false;
if ($key != $day) continue;
$found_date = true;
// scan for store
foreach ($date as $item){
$found_store = false;
if ($item['store'] != $store) continue;
$found_store = true;
// stop looping if store found
break;
}
// create null element
if (!$found_store) {
$date []= array(
"store" => $store
, "price" => null
);
}
// stop looping if date found
break;
}
// if date not found, create all elements
if (!$found_date) {
$history[$day]= array(
0 => array(
"store" => $store
, "price" => null
)
);
}
print_r($history);
之前：
Array
(
[2016-05-28] => Array
(
[0] => Array
(
[store] => 1
[price] => 12
)
[1] => Array
(
[store] => 7
[price] => 18
)
[2] => Array
(
[store] => 9
[price] =>
)
)
)
之后：
Array
(
[2016-05-28] => Array
(
[0] => Array
(
[store] => 1
[price] => 12
)
[1] => Array
(
[store] => 7
[price] => 18
)
[2] => Array
(
[store] => 9
[price] =>
)
[3] => Array
(
[store] => 8
[price] =>
)
)
)
感谢@trincot评论的帮助，我使用存储id作为数组中的键，完成了我想要做的事情，工作代码如下。
$setPriceHistoryData = $daoObj->getSetPriceHistoryData($set['id']);
$chartDays = date('Y-m-d', strtotime('-30 days'));
$endDay = date('Y-m-d');
$priceHistoryData = array();
while ($chartDays <= $endDay) {
for ($i = 0; $i < count($setPriceData["price_history_store_data"]); $i++) {
$store = $setPriceData["price_history_store_data"][$i]["id"];
for ($j = 0; $j < count($setPriceHistoryData); $j++) {
if ($store == $setPriceHistoryData[$j]["vph_store"]
&& $chartDays == $setPriceHistoryData[$j]["vph_date"]
&& !isset($priceHistoryData[$chartDays][$store])) {
$priceHistoryData[$chartDays][$store] = $setPriceHistoryData[$j]["vph_price"];
} else {
if (!isset($priceHistoryData[$chartDays][$store])) {
$priceHistoryData[$chartDays][$store] = null;
}
}
}
}
// Increment day
$chartDays = date('Y-m-d', strtotime("+1 day", strtotime($chartDays)));
}
<?php
$history = array(); // Assuming that's array's identifier.
$history['2016-05-28'] = array (
array('store' => 1, 'price' => 12),
array('store' => 7, 'price' => 18),
array('store' => 9, 'price' => 20)
);
// variables for the if condition
$day = '2016-05-28';
$store = 8;
$match_found = FALSE;
foreach($history[$day] as $element) {
if ($element['store'] == $store) {
$match_found = TRUE;
}
else {
continue;
}
}
if ($match_found == TRUE) {
// I included a break statement here. break works only in iterations, not conditionals.
} else {
array_push($history[$day], array('store' => $store, 'price' => null));
// I was pushing to $history[$date] instead of $history[$day] since the variable I created was $day, NOT $date
}
我重写了PHP代码段，只是因为键值声明中出现了一些错误。例如，根据PHP规范，2016-05-28键元素应该是字符串或整数(http://php.net/manual/en/language.types.array.php)
所以您的代码片段会像上面的代码一样出现
我编辑了代码，将数据附加到主日期元素中，而不是根
由于您愿意更改数据结构，一种不同的、非常酷的方法只需几行简单的代码就可以完成这项工作。首先将数据源更改为新形状，其中商店ID是关键，价格是值
$history = [
'2016-06-15'=>[
1=>10, 2=>10, //On June 15, store 1 had price 10
],
'2016-06-16'=>[
1=>10, 3=>10,
],
'2016-06-17'=>[
3=>10, 4=>10,
],
];
现在，您所要做的就是在源代码中循环使用天数，并在数组上使用+运算符添加任何丢失的存储(它会添加丢失的密钥(
$required_stores = [1,2,3,4]; // stores you wish to add if missing
//will be [1=>null, 2=>null, 3=>null, 4=>null]
$required_keys = array_combine(
$required_stores,
array_fill(0,count($required_stores),null)
);
//go through each day and add required keys if they're missing
foreach ($history as &$stores):
$stores += $required_keys
endforeach;
CCD_ 11通过使用第一参数作为键并且使用第二参数作为值来返回数组。