输出数组中的当前元素、下一个元素和上一个元素的值:
<?php $people = array ( "Peter" , "Joe" , "Glenn" , "Cleveland" ); echo current( $people ) . "<br>" ; echo next( $people ) . "<br>" ; echo prev( $people ); ?> |
prev() 函数将内部指针指向数组中的上一个元素,并输出。
相关的方法:
参数 | 描述 |
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array | 必需。规定要使用的数组。 |
返回值: | 如果成功则返回数组中上一个元素的值,如果没有更多的数组元素则返回 FALSE。 |
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PHP 版本: | 4+ |
所有相关方法的演示:
<?php $people = array ( "Peter" , "Joe" , "Glenn" , "Cleveland" ); echo current( $people ) . "<br>" ; // The current element is Peter echo next( $people ) . "<br>" ; // The next element of Peter is Joe echo current( $people ) . "<br>" ; // Now the current element is Joe echo prev( $people ) . "<br>" ; // The previous element of Joe is Peter echo end ( $people ) . "<br>" ; // The last element is Cleveland echo prev( $people ) . "<br>" ; // The previous element of Cleveland is Glenn echo current( $people ) . "<br>" ; // Now the current element is Glenn echo reset( $people ) . "<br>" ; // Moves the internal pointer to the first element of the array, which is Peter echo next( $people ) . "<br>" ; // The next element of Peter is Joe print_r (each( $people )); // Returns the key and value of the current element (now Joe), and moves the internal pointer forward ?> |