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HomeBackend DevelopmentPHP Tutorialphp的array数组和使用实例简明教程(容易理解)_PHP教程

注意注释部分的文字介绍哦~

复制代码 代码如下:
//实例化一个数组
$array = array();
//数组由两部分组成 如下
//array(键名[key]=>值[value])
//键名一般用与索引
//类型可以为 int 或 字符串[int是什么可以查php手册]
//所以可以这样写
//$array = array(0=>'a',1=>'b');
//你也可以这样写
//array会自动补充索引键名,默认是 int值 由0开始
$array = array('a','b');
//测试 不能用echo 只能用 print_r 打印数组  不要问为什么,做就对了
print_r($array);
//输出结果是  Array ( [0] => a [1] => b )
//可以看出,如果你不设定键名[key] 它会自动补充 key
//你也可以随意改变 key
$array = array(3=>'a',5=>'b');
print_r($array);
//结果 Array ( [3] => a [5] => b )
//如果你要读取数组的内容,你可以这么做
echo $array[3];
//结果是 a
//这里用echo 是因为只要不是数组,都可以直接用echo输出
//key可以为 字符串
$array = array('aa'=>'a','bb'=>'b');
print_r($array);
//结果是Array ( [aa] => a [bb] => b )
//所以你也可以 echo $array['aa']; 注意字符串都是要用引号括住
//值[value]可以是一个变量,可以是数组
$array = array(0=>array('a','b'),1=>array('c','d'));
print_r($array);
//结果是 Array ( [0] => Array ( [0] => a [1] => b ) [1] => Array ( [0] => c [1] => d ) )
//这叫二维数组
//读取里面的内容可以是这样
echo $array[0][1];
//结果是b 也可以用
//当然也可以是包含更多的数组
$array = array(0=>array(array('a','b'),array('c','d')),1=>array(array('e','f'),array('g','h')));
//看起来有点乱,要自己慢慢领悟
//回归到实际应用中 实例化一个数租
$array = array();
//模拟一个sql循环 sql多数是用 while循环,我这里做一个简单的for 10次循环
echo '
'; echo '
';
for($i=0;$i  $array[] = array('name'=>'我的名'.$i,'age'=>'我的年纪1'.$i);
  // $array[]  加中括号 是要让他生成10 个数组 分别0 - 10
  //如果是 $array = array('name'=>'我的名'.i,'age'=>'我的年纪1'.i);
  //那么结果只有一条数组。最后一条会代替了前一条
}
print_r($array);
//结果 Array ( [0] => Array ( [name] => 我的名0 [age] => 我的年纪10 ) [1] => Array ( [name] => 我的名1 [age] => 我的年纪11 ) [2] => Array ( [name] => 我的名2 [age] => 我的年纪12 ) [3] => Array ( [name] => 我的名3 [age] => 我的年纪13 ) [4] => Array ( [name] => 我的名4 [age] => 我的年纪14 ) [5] => Array ( [name] => 我的名5 [age] => 我的年纪15 ) [6] => Array ( [name] => 我的名6 [age] => 我的年纪16 ) [7] => Array ( [name] => 我的名7 [age] => 我的年纪17 ) [8] => Array ( [name] => 我的名8 [age] => 我的年纪18 ) [9] => Array ( [name] => 我的名9 [age] => 我的年纪19 ) [10] => Array ( [name] => 我的名10 [age] => 我的年纪110 ) )
//怎么用呢?
?>


      foreach ($array as $value) {
      echo '
  • '.$value['name'].'  |  '.$value['age'].'
  • ';
    }
      ?>

//以上结果加入了html代码,你举一反三吧
//如果你要对数组进行操作 例如 过滤上面的$array 里一共有10个数组,现在你要删除掉 key 为 3 的那一条
unset($array[3]);
print_r($array);
//你会看到  3的那个没有了
//以上是简单的用法,下次说些高级的
?>

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