php数组

';
print_r($arr);
var_dump($arr);
for ($i = 0; $i < count($arr); $i++) {
    echo $arr[$i];
    echo '
';
}
//关联数组

1.创建
$age = array(
    "peter" => "77",
    "ben" => "37",
    "joe" => "43"
    );
2.取值
echo $age['peter'] . "
";
foreach ($age as $key => $value) {
    echo $key . ":" . $value;
    echo "
";
}
foreach ($age as $k) { //一个值代表数值
    echo $k;
    echo "
";
}

sort($age);
foreach ($age as $key => $value) {
    echo "age[" . $key . "]:" . $value . "
";
}
3.排序
 "orange", 
        "b" => "banana", 
        "c" => "apple"
    );
    asort($fruits);
    foreach ($fruits as $key => $val) {
        echo "$key = $val\n";
}
    sort();//升序
    asort — 对数组进行排序并保持索引关系;按值排序
    ksort — 对数组按照键名排序
    rsort();//降序
    arsort — 对数组进行逆向排序并保持索引关系
    krsort — 对数组按照键名逆向排序
*/

/*键值对(key-value)*/
?>
<script>  //js的写法
    //js数组(字面量创建)
    var arr = [
        'zhang',
        'li',
        'wang'
    ];
    var arr_2 = new array(
        'zhang',
        'li',
        'wang'
    )
    var l = arr.length;
</script>