Php interview questions set-basic program questions

Basic Program questions


Print the time format of the previous day in PHP: 22:21:21

date('Y-m-d H:i:s', strtotime('-1 day'));

How to Implement string flip?
Method 1:

<?phpfunction reverse($var) {  $res = "";  for($i = 0, $j = strlen($var);$i<$j;$i++) {    $res = $var[$i].$res;  }  return $res;}$tmpvar = "wofang";$res = reverse($tmpvar);echo $res;?>

Method 2:

<?php echo strrev("Hello world!"); // outputs "!dlrow olleH" ?>

Write a function to traverse all files and subfolders in a folder.

<? Php/*** traverses the Directory and stores the result in an array. Php4 and above are supported. Php5 and later use the scandir () function to replace the while loop. * @ Param string $ dir * @ return array */function my_scandir ($ dir) {$ files = array (); if ($ handle = opendir ($ dir )) {while ($ file = readdir ($ handle ))! = False) {if ($ file! = '..' & $ File! = '. ') {If (is_dir ($ dir. '/'. $ file) {$ files [$ file] = rec_scandir ($ dir. '/'. $ file) ;}else {$ files [] = $ file ;}} closedir ($ handle); return $ files ;}}?>

Please write a function to verify that the email format is correct

<?phpfunction checkEmail( $email ) {    $preg = "/([a-z0-9]*[-_\.]?[a-z0-9]+)*@([a-z0-9]*[-_]?[a-z0-9]+)+[\.][a-z]{2,3}([\.][a-z]{2})?/i";    return preg_match( $preg, $email );}?>

There is a webpage address, such as the PHP development resources home page: http://www.phpres.com/index.html. how can I find my website content?
Method 1 (for php5 and later versions ):

<?php$readcontents = fopen('http://www.phpers.com/index.html');$contents = stream_get_contents($readcontents);fclose($readcontents);echo $contents;?>

Method 2:

<?php echo file_get_contents('http://www.phpers.com/index.html'); ?>

How to obtain the path of the script to be executed, including the obtained parameters.
Note: for example, there is a script www.domain.com, and the parameters passed to it include parameter 1, parameter 2, parameter 3 .... The method for passing parameters may be GET or POST,
So now please write like http://www.domain.com/script.php? Result of parameter 1 = value 1 & Parameter 2 = value 2...
No answer

Write a sorting algorithm, which can be Bubble sorting or fast sorting. Assume that the object to be sorted is a one-dimensional array.
(Note: you cannot use existing functions of the system. Remember the basic knowledge you have learned before)

<? Php/*** sorting class */class Sort {/** Bubble Sorting small to large */public function bubble_sort ($ array) {$ count = count ($ array ); if ($ count <= 0) return false; for ($ I = 0; $ I <$ count; $ I ++) {for ($ j = 1; $ j <= $ count-$ I-1; $ j ++) {if ($ array [$ j] <$ array [$ j-1]) {$ tmp = $ array [$ j]; $ array [$ j] = $ array [$ j-1]; $ array [$ j-1] = $ tmp; }}return $ array;}/*** Quick Sort */public function quick_sort ($ Rr) {$ len = count ($ arr); if ($ len <= 1) return $ arr; $ key = $ arr [0]; $ left_arr = $ right_arr = array (); for ($ I = 1; $ I <$ len; $ I ++) {if ($ arr [$ I] <= $ key) $ left_arr [] = $ arr [$ I]; else $ right_arr [] = $ arr [$ I];} $ left_arr = $ this-> quick_sort ($ left_arr); $ right_arr = $ this-> quick_sort ($ right_arr); return array_merge ($ left_arr, array ($ key ), $ right_arr);}/*** Hill sort */public func Tion shell_sort ($ datas) {// group for ($ increment = count ($ datas)/2; $ increment> 0; $ increment = $ increment/2) {// sort each group for ($ I = $ increment; $ I <count ($ datas); $ I ++) {$ temp = $ datas [$ I]; $ j = 0; for ($ j = $ I; $ j >=$ increment; $ j = $ j-$ increment) {if ($ temp <$ datas [$ j-$ increment]) {$ datas [$ j] = $ datas [$ j-$ increment];} else {break ;}$ datas [$ j] = $ temp ;}} return $ Datas ;}}?>

There is a table menu (mainmenu, submenu, url). Please use recursion to write a tree menu and list all menus.
No answer

You can write a program to find the maximum number.
No answer

There is an array $ a = array (, 2); sort it again and list it in ascending order.
No answer

Write two regular expressions that match the email address and URL. Similar to the following:
Email Address: user_name.first@example.com.cn
URL: http://www.example.cpm.cn/user_profile.php? Uid = 1, 100
(Note: The standard regular expression is the regular expression that can be parsed by the regular expression of the preg _ * class in php)
Email:/\ w + ([-+.] \ w +) * @ \ w + ([-.] \ w + )*\. \ w + ([-.] \ w + )*/;
URL:/^ http: \/[\ w] + \. [\ w] + [\ S] */

Write a piece of code in php. If no 3rd variables are used, the values of $ a and $ B are exchanged, and the initial values of $ a and $ B are set.

<?php    $a = 1;    $b = 2;    list($b, $a) = array($a, $b);?> 

Write a function to retrieve the file extension from a standard url as efficiently as possible.
Example: http://www.sina.com.cn/abc/de/fg.php? Id = 1 need to retrieve php or. php
Answer 1:

<?phpfunction getExt($url){  $arr = parse_url($url);  $file = basename($arr['path']);  $ext = explode(".", $file);  return $ext[1];}?>  

Answer 2:

<?phpfunction getExt($url) { $url = basename($url); $pos1 = strpos($url, "."); $pos2 = strpos($url, "?"); if(strstr($url, "?")){   return substr($url, $pos1 + 1, $pos2 - $pos1 - 1); } else {   return substr($url, $pos1); }}?>  

Write a function to calculate the relative path of the two files.
For example, $ a = '/a/B/c/d/e. php ';
$ B = '/a/B/12/34/c. php ';
The relative path of $ B relative to $ a should be ../c/d.

<?php   function getRelativePath( $a, $b ) {       $returnPath = array( dirname( $b ) );       $arrA = explode( '/', $a );       $arrB = explode( '/', $returnPath[0] );       for ( $n = 1, $len = count( $arrB ); $n < $len; $n++ ) {           if ( $arrA[$n] != $arrB[$n] ) {               break;           }       }       if ( $len - $n > 0 ) {           $returnPath = array_merge( $returnPath, array_fill( 1, $len - $n, '..' ) );       }       $returnPath = array_merge( $returnPath, array_slice( $arrA, $n ) );       return implode( '/', $returnPath );   }   echo getRelativePath( $a, $b );?>