php基础__2019-07-03

作者: 正周 | 来源:发表于2019-07-17 06:49 被阅读0次

php基础__2019-07-03
前言
PHP笔记
Alpine PHP Dockerfile
从0到1学习网络安全【目录】
程序员找工作必备 PHP 基础面试题（四）
一. PHP入门篇和PHP进阶篇
PHP开发实例大全（基础卷）
07-Ajax
PHP入门一

php数组原型

php数组其实是一种有序映射（或者说是有序字典）

<?php
/**
 * @author:Noah
 * noahlee0918@gmail.com
 * @param $arr
 * 使用each循环数组
 */
function eachArr($arr){
    reset($arr);
    while(list($key,$val) = each($arr)){
        echo $key . '=>' . $val.PHP_EOL;
    }
}


/**
 * @author:Noah
 * noahlee0918@gmail.com
 * @param $arr
 * @param $val
 * @return mixed
 * 使用数组指针取出当前值的下一个值，环形取
 */
function getNextValue($arr,$val){
    while($row = current($arr)){
        if($row == $val){
            if(next($arr) == false){
                return $val . '没有下一个值';
            }else{
                return $val . '下一个值是' .current($arr);
            }
        }
        next($arr);
    }
}

$listArr = [
    '1232','2456','7789','8976',
    '5678','3456','2347','9876',
    '3451','7744','2212','3214',
];
//eachArr($listArr);
$c_val = '3456';
$ret = getNextValue($listArr,'3456');
echo($ret);

##### 数组函数
//array_change_key_case将数组的所有键名修改为大写或者小写
$arr = array('aDc'=>1212,'aarrfggD'=>2323);
print_r(array_change_key_case($arr,CASE_UPPER));
print_r(array_change_key_case($arr,CASE_LOWER));

//array_chunk将一个数组分割成多个，第三个参数默认false，为true表示保留原来的键名
$arr_a = array('a','c','d','e','f','g','h');
print_r(array_chunk($arr_a,2,true));

//array_column 返回数组指定的一列，第三个参数可选，填写表示作为返回列的索引
$records = array(
    array('id' => 2135, 'first_name' => 'John', 'last_name' => 'Doe'),
    array('id' => 3245,'first_name' => 'Sally', 'last_name' => 'Smith'),
    array('id' => 5342, 'first_name' => 'Jane', 'last_name' => 'Jones'),
    array('id' => 5623,'first_name' => 'Peter', 'last_name' => 'Doe' )
);
print_r(array_column($records,'first_name'));
print_r(array_column($records,null,'id'));
print_r(array_column($records,'first_name','id'));

//array_combine  创建一个数组，用一个数组的值作为其键名，另一个数组的值作为其值
$arr_a_1 = array('zhang','li','wang');
$arr_a_2 = array('san','si','wu');
print_r(array_combine($arr_a_1,$arr_a_2));

//array_count_values  统计数组中所有的值
$arr_b = array(1, "hello", 1, "world", "hello");
print_r(array_count_values($arr_b));

//array_diff_assoc 带索引检查计算数组的差集
$array1 = array("a" => "green", "b" => "brown", "c" => "blue", "red");
$array2 = array("a" => "green", "yellow", 0=>"red");
$result = array_diff_assoc($array1, $array2);
print_r($result);

//array_diff_key 使用键名计算数组的差集
$result = array_diff_key($array1, $array2);
print_r($result);


//array_diff_uassoc 用用户提供的回调函数做索引检查来计算数组的差集
function diff_c($a,$b){
    if ($a === $b){
        return 0;
    }
    return ($a > $b) ? 1 : -1;
}
$arr1 = array('a'=>12121,'b'=>2323,'red');
$arr2 = array('a'=>12121,2323,'red');
print_r(array_diff_uassoc($arr1,$arr2,"diff_c"));


//array_diff 计算数组的差集
$array1 = array("a" => "green", "red", "blue", "red");
$array2 = array("b" => "green", "yellow", "red");
$result = array_diff($array1, $array2);

print_r($result);

//array_fill_keys使用指定的键和值填充数组
$arr1 = array('aaa'=>124,'ccc'=>333,'ddd'=>222,'hhh'=>5656);
$arr2 = array('eee'=>2323,'fff'=>3434,'ggg'=>4545);
print_r(array_fill_keys($arr1,$arr2));

// array_fill 用给定的值填充数组 第一个参数是第一个索引,若是负数,那它后一个索引从0开始;第二个为数量,第三个为值
$arr = array_fill(0,5,'a');
print_r($arr);

//array_filter用回调函数过滤数组中的单元
$arr = [1,2,3,4,5,6,7,8,9];
function odd($n){
    return $n & 1; //& :按位"与"运算,只有奇数(odd)才可以返回1,否则返回0
}
function even($n){
    return !($n & 1);//数组中除了奇数,剩下的就是偶数了
}

$arr1 = array_filter($arr, 'odd');
$arr2 = array_filter($arr, 'even');

print_r($arr1);
print_r($arr2);

//array_flip交换数组中的键和值
$arr1 = array('ddd'=>1,'fff','ty'=>'eeee');
print_r(array_flip($arr1));

//array_intersect_assoc 带索引检查计算数组的交集
$array1 = array("a" => "green", "b" => "brown", "c" => "blue", "red");
$array2 = array("a" => "green", "b" => "yellow", "blue", "red");
$result_array = array_intersect_assoc($array1, $array2);
print_r($result_array);

//array_intersect_key 使用键名比较计算数组的交集
$array1 = array('blue'  => 1, 'red'  => 2, 'green'  => 3, 'purple' => 4);
$array2 = array('green' => 5, 'blue' => 6, 'yellow' => 7, 'cyan'   => 8);

print_r(array_intersect_key($array1, $array2));


//array_intersect_uassoc 带索引检查计算数组的交集，用回调函数比较索引
$array1 = array("a" => "green", "b" => "brown", "c" => "blue", "red");
$array2 = array("a" => "GREEN", "B" => "brown", "yellow", "red");

print_r(array_intersect_uassoc($array1, $array2, "strcasecmp"));


//array_intersect_ukey 用回调函数比较键名来计算数组的交集
function key_compare_func($key1, $key2)
{
    if ($key1 == $key2)
        return 0;
    else if ($key1 > $key2)
        return 1;
    else
        return -1;
}

$array1 = array('blue'  => 1, 'red'  => 2, 'green'  => 3, 'purple' => 4);
$array2 = array('green' => 5, 'blue' => 6, 'yellow' => 7, 'cyan'   => 8);

print_r(array_intersect_ukey($array1, $array2,'key_compare_func'));


//array_intersect计算两个数组的交际
$array1 = array("a" => "green", "red", "blue");
$array2 = array("b" => "green", "yellow", "red");
print_r(array_intersect($array1,$array2));

//array_key_exists 检查数组里是否有指定的键名或索引
$array1 = array("a" => "green", "red", "blue",'hh'=>999);
var_dump(array_key_exists('a',$array1));

//array_key_first 获取数组的第一个键
$array = ['abc' => 1, 'bcd' => 2, 'cde' => 3];
print_r(array_key_first($array));


//array_keys返回数组中部分的或所有的键名
$array = array(0 => 100, "color" => "red");
print_r(array_keys($array));

$array1 = array("blue", "red", "green", "blue", "blue");
print_r(array_keys($array1, "blue"));


//array_map  为数组的每个元素应用回调函数
function sumc($n){
    return ($n * $n * $n);
}
$arr = [1,2,3,4];
$a = array_map('sumc',$arr);
print_r($a);