PHP array operations subtotal

Manipulating arrays in PHP is the most basic and commonly used operation. PHP has many built-in convenient functions for us to use. However, the translation of official documents is sometimes not so easy to understand, and some functions usually require a lot of concepts to be understood every once in a while. mix. A good memory is not as good as a bad writing. I will slowly record some functions that I usually use here, and do demos just to understand how to use them.

1. Array merging

Array merging is originally a very simple thing, but the simpler something is, the easier it is to forget, especially when it is rarely used. . . .

<?php
echo "<PRE>";
$a=[1,2,3];
$b=[4,5,6];
//1.PHP数组合并函数
$c=array_merge($a,$b);
var_dump($c);
//2.直接数组相加 有顺序 按照键覆盖，后面键覆盖前面键的值
$c=$a+$b;
var_dump($c);
//3.
$c=$b+$a;
var_dump($c);

//4.这种给大家理解一下push，是不行的
array_push($a,$b);
var_dump($a);

results:

1.
array(6) {
  [0]=>
  int(1)
  [1]=>
  int(2)
  [2]=>
  int(3)
  [3]=>
  int(4)
  [4]=>
  int(5)
  [5]=>
  int(6)
}
2.
array(3) {
  [0]=>
  int(1)
  [1]=>
  int(2)
  [2]=>
  int(3)
}
3.
array(3) {
  [0]=>
  int(4)
  [1]=>
  int(5)
  [2]=>
  int(6)
}
4.
array(4) {
  [0]=>
  int(1)
  [1]=>
  int(2)
  [2]=>
  int(3)
  [3]=>
  array(3) {
    [0]=>
    int(4)
    [1]=>
    int(5)
    [2]=>
    int(6)
  }
}

The above has introduced a subtotal of PHP array operations, including aspects of it. I hope it will be helpful to friends who are interested in PHP tutorials.