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HomeBackend DevelopmentPHP TutorialExplain relevant examples of PHP array traversal

Traverse the array: It means going through each one once. This article will explain the relevant examples.

1) for loop

is rarely used because it has defects

<!--?php
/*
 使用for循环可以遍历数组
*/
/*
count(数组[,1])返回数组里面数据的个数,还可以获取多维数组的个数 ,当然一般我们只传一个数组进去就可以了
$arr1=array(
        array(1,2,3),
        array(4,5,6)
);
echo count($arr1,1);//2+6=8
*/
$arr=array(
    &#39;a&#39;,&#39;b&#39;,&#39;c&#39;,&#39;d&#39;,&#39;e&#39;,&#39;f&#39;
);
for($i=0;$i<count($arr);$i++){
    echo $arr[$i];
}

2)foreach语句来实现遍历数组的目的 foreach(数组变量 as 变量1){ //每次循环执行的语句 变量1代表当前正在经历(访问)的数据 } foreach(数组变量 as 变量1=>变量2){ //每次循环执行的语句 变量1代表当前正在经历(访问)的数据的索引值 变量1代表当前正在经历(访问)的数据 } 

<!--?php
/*
 * foreach来遍历我们的数组
 * 这个比较常用,因为是专门为我们来遍历数组的!
 * */
$arr1=array(
        &#39;name&#39;=-->'傻逼',
        'num'=>10
);
/*
foreach($arr1 as $value){
    echo $value.'
';
}
*/
foreach($arr1 as $key=>$value){
    echo $key.'=>'.$value.'
';
}
?>
<!--?php
/*
 * 以后遇到这种情况,咱们到时候再说 - 递归思想的解决
 * */
$arr=array(
    &#39;a&#39;,
    &#39;b&#39;,
    &#39;c&#39;,
    &#39;d&#39;,
    array(
        1,2,3,4,5
    )
);
foreach ($arr as $val){
    var_dump($val);
}
?-->
<!--?php
/*
 * 有规律,我们可以直接foreach嵌套去遍历就可以了
 * */
$arr=array(
    array(&#39;a&#39;,&#39;b&#39;,&#39;c&#39;,&#39;d&#39;),
    array(&#39;a&#39;,&#39;b&#39;,&#39;c&#39;,&#39;d&#39;,&#39;e&#39;,&#39;f&#39;),
    array(&#39;a&#39;,&#39;b&#39;,&#39;c&#39;,&#39;d&#39;,&#39;f&#39;),
    array(&#39;a&#39;,&#39;b&#39;,&#39;c&#39;,&#39;d&#39;),
);
foreach ($arr as $val1){
    foreach ($val1 as $val2){
        echo $val2.&#39;<br /-->&#39;;
    }
}
?>
<!--?php
/**
 * */
$students=array(
    array(&#39;傻逼&#39;,1,true,60.5),
    array(&#39;坑逼&#39;,2,true,80.5),
    array(&#39;菜逼&#39;,3,false,85.5)
);
echo &#39;<table border=1-->&#39;;
foreach ($students as $val){
    if($val[2]===true){
        $val[2]=&#39;男&#39;;
    }else{
        $val[2]=&#39;女&#39;;
    }
    echo "{$val[0]}{$val[1]}{$val[2]}{$val[3]}";
}
echo &#39;&#39;;
?>

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