PHP foreach循環(huán)

foreach循環(huán)用于遍歷數(shù)組元素。愛(ài)掏網(wǎng) - it200.com它只適用于數(shù)組和對(duì)象。愛(ài)掏網(wǎng) - it200.com如果嘗試將其用于不同數(shù)據(jù)類(lèi)型的變量，將會(huì)出現(xiàn)錯(cuò)誤。愛(ài)掏網(wǎng) - it200.com

foreach循環(huán)根據(jù)元素而不是索引進(jìn)行工作。愛(ài)掏網(wǎng) - it200.com它提供了一種最簡(jiǎn)單的方法來(lái)迭代數(shù)組的元素。愛(ài)掏網(wǎng) - it200.com

在foreach循環(huán)中，我們不需要遞增值。愛(ài)掏網(wǎng) - it200.com

語(yǔ)法

foreach (array asvalue) {
    //code to be executed
}

還有一種foreach循環(huán)的語(yǔ)法。愛(ài)掏網(wǎng) - it200.com

語(yǔ)法

foreach (array askey => $element) { 
    //code to be executed
}

流程圖

示例1

使用foreach循環(huán)打印數(shù)組元素的PHP程序。愛(ài)掏網(wǎng) - it200.com

<?php
    //declare array
    season = array ("Summer", "Winter", "Autumn", "Rainy");

    //access array elements using foreach loop
    foreach (season as element) {
        echo "element";
        echo "</br>";
    }
?>

輸出：

Summer 
Winter 
Autumn 
Rainy

示例2

使用foreach循環(huán)打印關(guān)聯(lián)數(shù)組元素的PHP程序。愛(ài)掏網(wǎng) - it200.com

<?php
    //declare array
    employee = array (
        "Name" => "Alex",
        "Email" => "alex_jtp@gmail.com",
        "Age" => 21,
        "Gender" => "Male"
    );

    //display associative array element through foreach loop
    foreach (employee as key =>element) {
        echo key . " : " .element;
        echo "</br>";   
    }
?>

輸出：

Name : Alex
Email : stash
Age : 21
Gender : Male

示例3

多維數(shù)組

<?php
    //declare multi-dimensional array
    a = array();a[0][0] = "Alex";
    a[0][1] = "Bob";a[1][0] = "Camila";
    a[1][1] = "Denial";

    //display multi-dimensional array elements through foreach loop
    foreach (a as e1) {
        foreach (e1 as e2) {
            echo "e2\n";
        }
    }
?>

輸出：

Alex Bob Camila Denial

示例4

動(dòng)態(tài)數(shù)組

<?php
    //dynamic array
    foreach (array ('j', 'a', 'v', 'a', 't', 'p', 'o', 'i', 'n', 't') as elements) {
        echo "elements\n";
    }
?>

輸出:

j a v a t p o i n t