php数组相关转化、函数练习，php数组转化函数
$arr1=array(
0 => Array('子题目' => '11'),
1 => Array('答案' => 'ada'),
2 => Array('解析' => '3a'),
3 => Array('子题目' => '121'),
4 => Array('答案' => 'aa'),
5 => Array('解析' => '3a'),
6 => Array('子题目' => '11'),
7 => Array('答案' => 'aa'),
8 => Array('解析' => '3da'),
);
// 将数组 $arr1 转化成 $arr2;
$arr2=array(
0 => Array('子题目' => '11','答案' => 'ada','解析' => '3a'),
1 => Array('子题目' => '121','答案' => 'aa','解析' => '3a'),
2 => Array('子题目' => '11','答案' => 'aa','解析' => '3da'),
);
// 方法1，利用array_chunk和array_merge()函数;
$arr3 = array();
$arr4 = array_chunk($arr1,3); // 将数组分割成 组成小数组，每三个数组元素代表一个小数组;
// 注意：此时省略了最后一个参数preserve keys = false参数，默认健名不受保护，即：每个chunk的小数组元素将从0开始索引(关联数组也是从0开始);
foreach($arr4 as $keys => $values){
$arr3[$keys] = array_merge($values[0],$values[1],$values[2]);
}
print_r($arr3);
// 方法2： 利用 array_splice()函数和 array_merge()函数;
$arr3 = array();
while(0<count($arr1)){
$temp = array_splice($arr1,0,3);
$arr3[] = array_merge($temp[0],$temp[1],$temp[2]); // 对数组的融合;
}
print_r($arr3);
// 方法3： 利用 foreach双层遍历后的健名和值，再结合count函数;
$arr3 = array();
foreach($arr1 as $keys => $values){
foreach($values as $ks => $vs){
$arr4[$ks] = $vs;
}
if(count($arr4)==3){
$arr3[] = $arr4;
$arr4 = array();
}
}
print_r($arr3);
// 方法4： 利用 foreach双层遍历后的健名和值,再结合if语句;
$arr3 = array();
$i = 0;
$j = 0;
foreach($arr1 as $keys => $values){
foreach($values as $ks => $vs){
$arr3[$i][$ks] = $vs;
$j++;
}
if($j%3==0){
$i++;
}
}
print_r($arr3);
// 方法4： 利用 foreach双层遍历后的健名和值,再结合if...else if语句;
$arr3 = array();
$i = 0;
foreach($arr1 as $key => $values){
foreach($values as $ks => $vs){
if($key==0){
$arr3[$i][$ks]=$vs;
}else if($key%3!=0){
$arr3[$i][$ks] = $vs;
}else{
$i++;
$arr3[$i][$ks] = $vs;
}
}
}
print_r($arr3);// array_combine()构造函数的方法;(和array_merge函数一样，都是针对的数组的值进行的操作)；
$i = $j = 0;
foreach($arr1 as $keys => $values){
foreach($values as $ks => $vs){
$k[] = $ks;
$v[] = $vs;
$i++;
if($i%3==0){
$arr3[$j] = array_combine($k,$v);
$k = $v = array();
$j++;
}
}
}
print_r($arr3);2、php二维数组转化;
$arr1 = array(
0 => array('confuguarable_sku' => '0572911','size' => 'XS'),
1 => array('confuguarable_sku' => '0572911','size' => 'S'),
2 => array('confuguarable_sku' => '0572911','size' => 'M'),
3 => array('confuguarable_sku' => '0575213','size' => 25),
4 => array('confuguarable_sku' => '0575213','size' => 26),
5 => array('confuguarable_sku' => '0575213','size' => 25),
6 => array('confuguarable_sku' => '0574843','size' => 28),
7 => array('confuguarable_sku' => '0574843','size' => 30),
8 => array('confuguarable_sku' => '0575494','size' => 'S')
);
//输出结果为
/*****
array(
0 => array('confuguarable_sku' => '0572911','size' => 'XS','S','M'),
1 => array('confuguarable_sku' => '0575213','size' => 25,26),
2 => array('confuguarable_sku' => '0574843','size' => 28,30),
3 => array('confuguarable_sku' => '0575494','size' => 'S')
);
******/
$arr2 = $arrtemp = array();
foreach($arr1 as $keys => $values){
$arrtemp[$values['confuguarable_sku']][] = $values['size'];
}
foreach($arrtemp as $kss => $vss){
$arr2[] = array('confuguarable_sku' => $kss,'size' => implode(',',array_unique($vss)));
}
print_r($arr2);
2、php二维数组整合并求和;
$arr3=[
['id'=>1,'name'=>'php','num'=>3],
['id'=>2,'name'=>'js','num'=>1],
['id'=>1,'name'=>'php','num'=>2],
['id'=>3,'name'=>'python','num'=>2],
];
//怎么对id相同的对num求和并去重，返回的结果为;
$arr=[
['id'=>1,'name'=>'php','num'=>5],
['id'=>2,'name'=>'js','num'=>1],
['id'=>3,'name'=>'python','num'=>2],
];
$result = [];
foreach ($arr3 as $v) {
if (isset($result[$v['id']])) {
$result[$v['id']]['num'] += $v['num'];
}
/******* 用array_key_exists()函数：判断健名是否存在数组中;
if(array_key_exists($v['id'],$result)){
$result[$v['id']]['num'] += $v['num'];
}
*********/
else {
$result[$v['id']] = $v;
}
}
print_r(array_values($result));
$arr5 = array(
array('num'=>5,'period'=>3),
array('num'=>10,'period'=>3),
array('num'=>15,'period'=>9)
);
// 对period相同的值的数组，对num求和，怎么处理变成：
$arr6 = array(
array('num'=>15,'period'=>3),
array('num'=>15,'period'=>9)
);
// 方法1： 找出数组中的相同值,用这个值作为新数组的健名(新数组的值如果之前没有相同值，即相同健名的时候，保持原数组；如果之前有相同的值，则对应的元素值相加)；
$arr2 = array();
foreach($arr5 as $keys => $values){
if(array_key_exists($values['period'],$arr2)){
$arr2[$values['period']]['num'] += $values['num'];
}else{
$arr2[$values['period']] = $values;
}
}
//print_r(array_values($arr2));
// 方法2：将相同元素作为一个新临时数组健名，值还是一个数组（分别为原始数组中，需要相加值的各个元素），
$arr7 = $temparr = array();
foreach($arr5 as $keys => $values){
$temparr[$values['period']][] = $values['num'];
}
//print_r($temparr);
foreach($temparr as $ks => $vs){
$arr7[] = array('num'=>array_sum($vs),'period'=>$ks);
}
//print_r($arr7);
// 方法3：以相同的元素作为一个新的健名,值为相同num内容的相加;
$result = $temp = array();
foreach($arr5 as $kks => $vvs){
list($n,$p) = array_values($vvs);
$temp[$p] = array_key_exists($p,$temp) ? ($temp[$p]+$n): $n;
}
foreach($temp as $kkk => $vvv){
$result[] = array('num' => $vvv,'period' => $kkk);
}
print_r($result);$oldarr = [
['a', 1],
['', 2],
['', 3],
['b', 4],
['', 5],
['c',6],
['',7]
];
/****** 转换为
$newarr = [
'a'=>'1,2,3',
'b'=>'4,5',
'c'=>'6,7'
];
********/
$arr2 = array();
foreach($oldarr as $keys => $values){
if($values[0]){ // 分别判读 第一个元素是 abc 还是 '';
$abc = $values[0]; // 此时必须赋值,保持健名为abc；不然不执行条件判读语句的时候,直接用 $values[0] 则表示的是''；
$arr2[$abc] = $values[1];
continue; // continue；跳出这个循环，进入下一循环（循环内后面的语句则不再执行）;
}
$arr2[$abc] .= ','.$values[1];
}
print_r($arr2);$arr8 = Array(
0 => Array('id' => 1,'department' => '市场' ),
1 => Array('id' => 1,'department' => '市场' ),
2 => Array('id' => 1,'department' => '市场' ),
3 => Array('id' => 2,'department' => '办公室'),
4 => Array('id' => 2,'department' => '办公室' ),
5 => Array('id' => 2,'department' => '办公室' ),
6 => Array('id' => 3,'department' => '收发室')
);
/******
循环后这样显示
id department 统计
1 市场 3
2 办公室 3
3 收发室 1
*******/
$arr9 = array();
foreach($arr8 as $keys => $values){
if(isset($arr9[$values['id']])){
$arr9[$values['id']]['count'] += 1;
}else{
$arr9[$values['id']] = $values;
$arr9[$values['id']]['count'] = 1;
}
}
foreach($arr9 as $kks => $vvs){
echo 'id='.$vvs['id'].' department='.$vvs['department'].' 统计='.$vvs['count'];
echo '<br/>';
}$arr10 = Array(0 => Array('initial' => 'A','typename' => '奥迪'),
1 => Array('initial' => 'F','typename' =>'F1'),
2 => Array('initial' => 'F','typename' => 'F2')
);
//怎么根据initial相同的分到同一个里面
/****
A{[0] => Array([initial] => A,[typename] => 奥迪)}
F{[0] => Array([initial] => F,[typename] =>F1),
[1] => Array([initial] => F,[typename] => F2)
}
******/
$arr11 = array();
foreach($arr10 as $keys => $values){
$arr11[$values['initial']][] = $values;
}
print_r($arr11);$arr8 = array(
array('id'=>1,'name'=>'小明','time'=>'1'),
array('id'=>1,'name'=>'小明','time'=>'2'),
array('id'=>1,'name'=>'小明','time'=>'3'),
array('id'=>2,'name'=>'小写','time'=>'4'),
array('id'=>3,'name'=>'小明','time'=>'5'),
array('id'=>2,'name'=>'小写','time'=>'6'),
array('id'=>5,'name'=>'小明','time'=>'7'),
);
//如何去除相同的id,保留第一个值,
//比如id=1的 保留 array('id'=>1,'name'=>'小明','time'=>'1'),其他相同的数组都删掉;
$arr9 = array();
foreach($arr8 as $keys => $values){
if(array_key_exists($values['id'],$arr9)){
continue;
}
$arr9[$values['id']] = $values;
}
//print_r($arr9);$arr7 = array(
array('user_id'=>1,'brand_id'=>'aaa','brand_name'=>'1'),
array('user_id'=>1,'brand_id'=>'aaa','brand_name'=>'2'),
array('user_id'=>1,'brand_id'=>'aaa','brand_name'=>'3'),
array('user_id'=>2,'brand_id'=>'ddd','brand_name'=>'4'),
array('user_id'=>3,'brand_id'=>'ddd','brand_name'=>'5')
);
$newarr = array();
foreach($arr7 as $_arr){
if(!isset($newarr[$_arr['user_id']])){
$newarr[$_arr['user_id']] = $_arr;
}
}
//print_r($newarr);
$a1=array('0' => array( "id" => '1', 'name'=>'aa' ),'1' => array( "id" => '2', 'name'=>'bb' ));
$a2=array('0' => array( "id" => '1', 'pwd'=>'888' ),'1' => array( "id" => '2', 'pwd'=>'999' ));
/******
合并成：
$a1_a2=array(
'0' => array( "id" => '1', 'name'=>'aa' , 'pwd'=>'888' ),
'1' => array( "id" => '2', 'name'=>'bb' , 'pwd'=>'999' ),
);
******/
$a1new = array();
$a2new = array();
$newarray = array();
foreach($a1 as $keys => $values){
$a1new[$values['id']] = $values['name']; // array(1=>'aa',2=>'bb');
}
foreach($a2 as $keys => $values){
$a2new[$values['id']] = $values['pwd']; // array(1=>'888',2=>'999');
}
foreach($a1new as $keys => $values){
$newarray[] = array('id'=>$keys,'name'=>$values,'pwd'=>isset($a2new[$keys])? $a2new[$keys]:'');
}
print_r($newarray);3、php二维数组排序；
//假如有以下数组：
$beforeSort = [
"0" => ["name" => "张三", "english" => 80, "chinese" => 60, "math" => 50 ],
"1" => ["name" => "李四", "english" => 50, "chinese" => 60, "math" => 70 ],
"2" => ["name" => "老王", "english" => 30, "chinese" => 50, "math" => 80 ],
];
// 现在需要在数组中按照 chinese 顺序，假如有相同，就按 math 顺序，最后得到的应该是如下的数组：
$afterSort = [
"2" => ["name" => "老王", "english" => 30, "chinese" => 50, "math" => 80 ],
"0" => ["name" => "张三", "english" => 80, "chinese" => 60, "math" => 50 ],
"1" => ["name" => "李四", "english" => 50, "chinese" => 60, "math" => 70 ],
];
// 方法1：利用 array_multisort 函数;
$chinese = $math = array();
foreach($beforeSort as $keys => $values){
$chinese[$keys] = $values['chinese']; // $chinese = array(0=>60,1=>60,2=>50);
// 等价于：
//$chinese = array_column($beforeSort,'chinese');
$math[$keys] = $values['math']; // $math = array(0=>60,1=>70,2=>80);
// 等价于：
//$math = array_column($beforeSort,'math');
}
array_multisort($chinese,SORT_ASC,$math,SORT_ASC,$beforeSort); // 对$beforeSort数组进行排序，先按照$chinese的升序，再按照$math的升序；
print_r($beforeSort);
// 方法2： 利用usort函数；// 注意：在第一个参数小于，等于或大于第二个参数时，该比较函数必须相应地返回一个小于，等于或大于 0 的整数；
function myfun1($a,$b){
if($a['chinese'] == $b['chinese'] ){
return 0;
}
return ($a['chinese'] > $b['chinese']) ? 1 : -1;
}
function myfun2($a,$b){
if($a['math'] == $b['math'] ){
return 0;
}
return ($a['math'] < $b['math']) ? 1 : -1;
}
usort($beforeSort,'myfun1'); // 满足了 > (1) 条件，所以chinese 从小到大排序；
usort($beforeSort,'myfun2'); // 不满足 (<) (-1) 的条件，所以 math 从大到小排序;(在第一次排序的基础上);
print_r($beforeSort);4、php二维数组去重;
$arr4=array(1=>array('a','b'),
2=>array('a','c'),
3=>array('a','b'));
//只输出第一项(第一项和第三项相同，去第三项)和第二项这个怎么解决？
foreach($arr4 as $keys => $values){
$arr5[$keys] = implode(' ',$values);
}
$arr5 = array_unique($arr5);
foreach($arr5 as $ks => $vs){
$arr6[$ks] = explode(' ',$vs);
}
print_r($arr6);$tid='1,2,2,4,4,5';
//变为$tid='1,2,4,5';
$arr = explode(',',$tid);
echo implode(',',array_unique($arr));
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