PHP数组学习之如何以合并方式创建数组

有两个数组
array (size=2)
  'a' => string 'red' (length=3)
  'b' => string 'green' (length=5)
array (size=2)
  'c' => string 'blue' (length=4)
  'd' => string 'yellow' (length=6)
  
合并两个数组
array (size=4)
  'a' => string 'red' (length=3)
  'b' => string 'green' (length=5)
  'c' => string 'blue' (length=4)
  'd' => string 'yellow' (length=6)

<?php
header("Content-type:text/html;charset=utf-8");
$keys=array("a","b","c","d");
$values=array("red","green","blue","yellow");
var_dump($keys);
var_dump($values);
echo "使用array_combine()合并数组后:";
var_dump(array_combine($keys,$values));
?>

<?php
$keys=array("a","b","c","d");
$values=array("red","green","blue");
var_dump(array_combine($keys,$values));
?>

<?php
$keys=array(array("1","2","3"),"b","c","d");
$values=array("red","green","blue","yellow");
var_dump(array_combine($keys,$values));
?>

<?php
$keys=array("a","b","c","d");
$values=array(array("red","pink","orange"),"green","blue","yellow");
var_dump(array_combine($keys,$values));
?>