PHP 数组

Posted 2020-11-06 xsr7yer

<?php

/*

PHP中，有三种素组类型：
* 索引数组 - 带有数字索引的数组
* 关联数组 - 带有指定键的数组
* 多维数组 - 包含一个或多个数组的数组

*/

#索引是自动分配的(索引从0开始):
$cars = array("Volvo", "BMW", "SAAB");
echo "I like " , $cars[0]. ", " . $cars[1]. " and " . $cars[2] . ".";
echo "<br>";

#也可以手动分配索引:
$cars2[0] = "Volvo";
$cars2[1] = "BMW";
$cars2[2] = "SAAB";
var_dump($cars2);
echo "<br>";

# 获取数组的长度 - count()函数
echo count($cars);
echo "<br>";

#遍历索引数组
$cars3 = array("Volvo", "BMW", "SAAB");
$arrlength = count($cars3);

for($x = 0; $x < $arrlength; $x++) {
	echo $cars3[$x];
	echo "<br>";
}

echo "<br>";

/*
PHP 关联数组
关联数组是使用您分配给数组的指定键的数组

有两种创建关联数组的方法:
*/

#第一种
$age = array("Peter"=>"35", "Ben"=>"37", "Joe"=>"43");
var_dump($age);

echo "<br>";

#第二种
$age2[‘Peter‘] = "35";
$age2[‘Ben‘] = "37";
$age[‘Joe‘] = "43";
var_dump($age);

echo "<br>";

echo "Peter is " . $age[‘Peter‘] . " years old.";
echo "<br>";

# 遍历关联数组

foreach($age as $x=>$x_value) {
	echo "Key = " . $x . ", Value = " . $x_value;
	echo "<br>";
}


?>

　结果回显：