Home >Backend Development >PHP Tutorial >Android programmers learn PHP development (20)-Arrays (2) Multi-dimensional arrays and practical applications-PhpStorm

Android programmers learn PHP development (20)-Arrays (2) Multi-dimensional arrays and practical applications-PhpStorm

黄舟Original: 2017-03-03 09:30:241152browse

In PHP development, a large proportion of us are operating arrays, so learning arrays is very important~~

<?php
    /**
     * 二维数组
     */
    $group = array(
        array("name"=>"iwanghang", "age"=>18, "sex"=>"男", "email"=>"iwanghang@qq.com"),  // $group[0]
        array("name"=>"queen", "age"=>14, "sex"=>"女", "email"=>"queen@qq.com"), // $group[1]
        array("name"=>"king", "age"=>55, "sex"=>"男", "email"=>"king@qq.com"), // $group[2]
        "four"=>array("name"=>"xiaoming", "age"=>8, "sex"=>"男", "email"=>"xiaoming@qq.com")
    );
    var_dump($group[1]); // 打印结果 ： array(4) { ["name"]=> string(5) "queen" ["age"]=> int(14)
                         // ["sex"]=> string(3) "女" ["email"]=> string(12) "queen@qq.com" }
    echo "<br>";
    var_dump($group[1]["name"]); // 打印结果 ： string(5) "queen"
    echo "<br>";
    var_dump($group[2]["age"]); // 打印结果 ： int(55)
    echo "<br>";
    var_dump($group["four"]["email"]); // 打印结果 ： string(15) "xiaoming@qq.com"
    echo "<br>";

<?php
    /**
     * 销毁指定下标Demo
     * isset 检测变量是否存在
     * unset 销毁指定的变量
     */
    echo &#39;---------- $arr = ["one", "two", "three". "four"]; ----------<br>&#39;;
    $arr = ["one", "two", "three", "four"];

    echo &#39;---------- isset($arr[2]) ----------<br>&#39;;
    if (isset($arr[2])){ // 打印结果：存在
        echo "存在";
    }else{
        echo "不存在";
    }
    echo "<br>";

    echo &#39;---------- print_r($arr) ----------<br>&#39;;
    print_r($arr); // 打印结果：Array ( [0] => one [1] => two [2] => three [3] => four )
    echo "<br>";

    echo &#39;---------- unset($arr[2]) ----------<br>&#39;;
    unset($arr[2]);
    if (isset($arr[2])){ // 打印结果：不存在
    echo "存在";
    }else{
        echo "不存在";
    }
    echo "<br>";

    echo &#39;---------- print_r($arr) ----------<br>&#39;;
    print_r($arr); // 打印结果：Array ( [0] => one [1] => two [3] => four )
    echo "<br>";

    echo &#39;---------- $arr[2] = null ----------<br>&#39;;
    $arr[2] = null;
    if (isset($arr[2])){ // 打印结果：不存在
        echo "存在";
    }else{
        echo "不存在";
    }
    echo "<br>";

    echo &#39;---------- print_r($arr) ----------<br>&#39;;
    print_r($arr); // 打印结果：Array ( [0] => one [1] => two [3] => four [2] => )
    echo "<br>";

<?php
    /**
     * 猴子选大王
     * xdw 选大王
     * count($arr) 数组下标
     */

    xdw(88,5); // 30只猴子，每3只出局1只

    function xdw($m, $n){
        $arr = array();

        $a = "a";

        for ($i=0; $i<$m; $i++){
            $arr[] = $a++;
        }

        print_r($arr);

        $i = 0;
        while (count($arr)>1){
            if ($i % $n == 0){
                echo $i."除以".$n."余数为0,所以删除".$arr[$i]."<br>";
                unset($arr[$i]);
            }else{
                $arr[] = $arr[$i];
                print_r($arr);
                echo "<br>";
                unset($arr[$i]);
            }
            $i++;
        }

        print_r($arr);
    }

The above is how Android programmers learn PHP development (20) - Array (2) Multidimensional arrays and practical applications - PhpStorm For more related content, please pay attention to the PHP Chinese website (www.php.cn)!

Statement：

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Previous article：Android programmers learn PHP development (19)-Basic concepts and definitions of arrays (1)-PhpStormNext article：Android programmers learn PHP development (19)-Basic concepts and definitions of arrays (1)-PhpStorm

See more

Android programmers learn PHP development (20)-Arrays (2) Multi-dimensional arrays and practical applications-PhpStorm

Related articles