在PHP中foreach的语法

本文介绍了在PHP中foreach的语法的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述 这个语法在php中是什么意思？ $ b $ p $ foreach $ meta $ t = $ $ data $ > 上面的$ t => $ data是什么意思。 因为foreach基本上是（例如来自w3school） code $ $ b $数组元$如下所示 $ b $ pre $ $ $ $ c > $ meta = Array（'facebook'=> Array（'title'=>'og：title'，'type'=>'og：type'， 'url'=>'og：url'，'thumbnail'=>'og：image'，'width'=>'og：image：width'， 'height'=>'og：image：height'，'sitename'=>'og：site_name'，'key'=>'fb：admins'， 'description'=>'og：description'），'twitter'=> Array（'card'=>'twitter：card'，'description'=>'twitter：description'，））; 那么$ t是什么，$ data是什么 如果我想在'脸谱'中获得'标题'作为一个单独的关键如何做到这一点。即。将 $ t => $ data => $ final work $ b $ t = facebook或twitter $ data = title等 $ final = og：title等 解决方案阅读 http://www.php.net/manual/en/control-structures.foreach.php ，关注示例。 / * foreach示例3：键和值* / $ a = array（one=> 1 ，two=> 2，three=> 3，seventeen=> 17 ）; foreach（$ a as $ k => $ v）{ echo\ $ a [$ k] => $ v.\\\; } / * foreach示例4：多维数组* / $ a = array（）; $ a [0] [0] =a; $ a [0] [1] =b; $ a [1] [0] =y; $ a [1] [1] =z; $ b foreach（$ a as $ v1）{ foreach（$ v1 as $ v2）{ echo$ v2\\\; 如果你使用php编码阅读官方手册不是'all-around-sites'。 已添加 one=> 1，two=> 2，three=> 3， seventeen=> 17 ）; foreach（$ a as $ k => $ v）{ echo$ k => $ v; //会显示 // one => 1two => 2three => 3 } foreach（$ a as $ v）{ echo$ v; //会显示 // 12317 code $ $ $ $ $ $ $ $ $ $ $ $ ，如果我们使用$ k（在我们的foreach（））中有'key'的名字。 $ v pre pre $ p $数组（'title'，&b; $ b'b'='>'$' 'og：type'，'url'=>'og：url'，'thumbnail'=>'og：image'，'width'=>'og ：image：width'，'height'=>'og：image：height'，'sitename'=>'og：site_name'，'key'=> 'fb：admins'，'description'=>'og：description'），'twitter'=> Array（'card'=>' twitter：card'，'description'=>'twitter：description'，））; $ b foreach（$ meta as $ sKey => $ aValue）{ // $ sKey =='facebook' // $ aValue = array（）$ b $ （$ aValue as $ sKeyInner => $ sValue）{ // $ sKeyInner =='$ b $ title' // $ sValue =='og：title'} } 就这样，我放弃了。 XD what does this syntax means in phpforeach ( $meta as $t => $data )what does $t => $data mean in the above. because foreach is basically (example from w3school) <?php $colors = array("red","green","blue","yellow"); foreach ($colors as $value) { echo "$value <br>"; } ?> it the above case $value represents $t => $data$colors represents $metathe array $meta is as follows $meta = Array( 'facebook' => Array( 'title' => 'og:title', 'type' => 'og:type', 'url' => 'og:url', 'thumbnail' => 'og:image', 'width' => 'og:image:width', 'height' => 'og:image:height', 'sitename' => 'og:site_name', 'key' => 'fb:admins', 'description' => 'og:description' ), 'twitter' => Array( 'card' => 'twitter:card', 'description' => 'twitter:description', ) );then what is $t and what is $data also if i want to get 'title' in 'facebook' as a seprate key how to do it. ie. will $t => $data => $final work $t = facebook or twitter $data = title etc $final = og:title etc 解决方案 Read this http://www.php.net/manual/en/control-structures.foreach.php , attention on examples./* foreach example 3: key and value */$a = array( "one" => 1, "two" => 2, "three" => 3, "seventeen" => 17);foreach ($a as $k => $v) { echo "\$a[$k] => $v.\n";}/* foreach example 4: multi-dimensional arrays */$a = array();$a[0][0] = "a";$a[0][1] = "b";$a[1][0] = "y";$a[1][1] = "z";foreach ($a as $v1) { foreach ($v1 as $v2) { echo "$v2\n"; }}PS: If you coding using php read official manual not 'all-around-sites'.ADDED$a = array( "one" => 1, "two" => 2, "three" => 3, "seventeen" => 17);foreach ($a as $k => $v) { echo "$k => $v"; // will show // one => 1two => 2three => 3}foreach ($a as $v) { echo "$v"; // will show // 12317}So, if we use $k (in our foreach()) we have 'key' name. In $v we always have 'value'.ADDED $meta = Array( 'facebook' => Array( 'title' => 'og:title', 'type' => 'og:type', 'url' => 'og:url', 'thumbnail' => 'og:image', 'width' => 'og:image:width', 'height' => 'og:image:height', 'sitename' => 'og:site_name', 'key' => 'fb:admins', 'description' => 'og:description' ), 'twitter' => Array( 'card' => 'twitter:card', 'description' => 'twitter:description', ) ); foreach ($meta as $sKey => $aValue) { // $sKey == 'facebook' // $aValue = array() // $aValue['title'] == 'og:title' foreach ($aValue as $sKeyInner => $sValue) { // $sKeyInner == 'title' // $sValue == 'og:title' } }That's all, I give up. XD 这篇关于在PHP中foreach的语法的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！