PHP编程题

1、实现中文字串截取无乱码的方法。(3分)
答:function GBsubstr($string, $start, $length) {
    if(strlen($string)>$length){
     $str=null;
     $len=$start+$length;
     for($i=$start;$i    if(ord(substr($string,$i,1))>0xa0){
     $str.=substr($string,$i,2);
     $i++;
    }else{
     $str.=substr($string,$i,1);
     }
    }
   return $str.'...';
    }else{
   return $string;
   }
}

2. 请写一个函数验证电子邮件的格式是否正确 (2分)
答:function checkEmail($email)
  {
    $pregEmail = "/([a-z0-9]*[-_\.]?[a-z0-9]+)*@([a-z0-9]*[-_]?[a-z0-9]+)+[\.][a-z]{2,3}([\.][a-z]{2})?/i";
    return preg_match($pregEmail,$email);  
  }

3、完成以下:
   (一)创建新闻发布系统，表名为message有如下字段 (3分)
　　id 文章id
　　title 文章标题
　　content 文章内容
　　category_id 文章分类id
    hits 点击量
答:CREATE TABLE 'message'(
   'id' int(10) NOT NULL auto_increment,
   'title' varchar(200) default NULL,
   'content' text,
   'category_id' int(10) NOT NULL,
   'hits' int(20),
   PRIMARY KEY('id');
   )ENGINE=InnoDB DEFAULT CHARSET=utf8;

    (二)同样上述新闻发布系统：表comment记录用户回复内容，字段如下 (4分)
　　comment_id 回复id
　　id 文章id，关联message表中的id
　　comment_content 回复内容
　　现通过查询数据库需要得到以下格式的文章标题列表,并按照回复数量排序，回复最高的排在最前面
　　文章id 文章标题 点击量 回复数量
　　用一个SQL语句完成上述查询，如果文章没有回复则回复数量显示为0
答:SELECT message.id id,message.title title,IF(message.`hits` IS NULL,0,message.`hits`) hits,
   IF(comment.`id` is NULL,0,count(*)) number FROM message LEFT JOIN 
   comment ON message.id=comment.id GROUP BY message.`id`;

　　(三)上述内容管理系统，表category保存分类信息，字段如下 (3分)
　　category_id int(4) not null auto_increment;
　　categroy_name varchar(40) not null;
　　用户输入文章时，通过选择下拉菜单选定文章分类
　　写出如何实现这个下拉菜单
答:function categoryList()
{
    $result=mysql_query("select category_id,categroy_name from category")
            or die("Invalid query: " . mysql_error());
    print("\n");
    while($rowArray=mysql_fetch_array($result))
    {
       print("".$rowArray['categroy_name']."\n");
    }
    print("");
}

4. 写一个函数，算出两个文件的相对路径

　　如 $a = '/a/b/c/d/e.php';
　　$b = '/a/b/12/34/c.php';
　　计算出 $b 相对于 $a 的相对路径应该是 http://www.cnblogs.com/c/d将()添上
答:function getRelativePath($a, $b) {   
    $returnPath = array(dirname($b));   
    $arrA = explode('/', $a);   
    $arrB = explode('/', $returnPath[0]);   
    for ($n = 1, $len = count($arrB); $n         if ($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); 

5.写一个函数，能够遍历一个文件夹下的所有文件和子文件夹。

答:
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] = scandir($dir . "/" . $file);
                 }else {
                     $files[] = $file;
                 }
             }
         }
         closedir($handle);
         return $files;
     }
}

6.简述论坛中无限分类的实现原理。
答:

//指定分类id变量$category_id,然后返回该分类的所有子类
//$default_category为默认的选中的分类
function Get_Category($category_id = 0,$level = 0, $default_category = 0)
{
 global $DB;
 $sql = "SELECT * FROM category ORDER BY categoryID DESC";
 $result = $DB->query( $sql );
 while ($rows = $DB->fetch_array($result)) 
 {
 $category_array[$rows[categoryParentID]][$rows[categoryID]] = array('id' => $rows[categoryID], 'parent' => $rows[categoryParentID], 'name' => $rows

[categoryName]);
 }
 if (!isset($category_array[$category_id]))
 {
 return "";
 }
 foreach($category_array[$category_id] AS $key => $category)
 { 
 if ($category['id'] == $default_category)
 {
 echo " }else
 {
 echo " }

 if ($level > 0)
 {
 echo ">" . str_repeat( " ", $level ) . " " . $category['name'] . "\n";
 }
 else
 {
 echo ">" . $category['name'] . "\n";
 }
 Get_Category($key, $level + 1, $default_category);
 }
 unset($category_array[$category_id]);
}

//指定分类id,然后返回数组
function Category_array($category_id = 0,$level=0)
{
 global $DB;
 $sql = "SELECT * FROM category ORDER BY categoryID DESC";
 $result = $DB->query($sql);
 while ($rows = $DB->fetch_array($result))
 {
 $category_array[$rows['categoryParentID']][$rows['categoryID']] = $rows;
 }

 foreach ($category_array AS $key=>$val)
 {
 if ($key == $category_id)
 {
 foreach ($val AS $k=> $v)
 {
 $options[$k] =
 array(
 'id' => $v['categoryID'], 'name' => $v['categoryName'], 'level' => $level, 'ParentID'=>$v['categoryParentID']
 );

 $children = Category_array($k, $level+1);

 if (count($children) > 0)
 {
 $options = $options + $children;
 }
 }
 }
 }
 unset($category_array[$category_id]);
 return $options;
}

?>

class cate
{

        function Get_Category($category_id = 0,$level = 0, $default_category = 0)
        {
             echo $category_id;
             $arr = array(
              '0' => array(
                             '1' => array('id' => 1, 'parent' => 0, 'name' => '1111'),
                             '2' => array('id' => 2, 'parent' => 0, 'name' => '2222'),
                            '4' => array('id' => 4, 'parent' => 0, 'name' => '4444')    
                          ),
              '1' => array(
                              '3' => array('id' => 3, 'parent' => 1, 'name' => '333333'),
                            '5' => array('id' => 5, 'parent' => 1, 'name' => '555555')     
                            ),
                          
              '3' => array(
                            '6' => array('id' => 6, 'parent' => 3, 'name' => '66666'),
                            '7' => array('id' => 7, 'parent' => 3, 'name' => '77777')
                            ),
              '4' => array(
                            '8' => array('id' => 8, 'parent' => 4, 'name' => '8888'),
                            '9' => array('id' => 9, 'parent' => 4, 'name' => '9999')
                            )    
             );

             if (!isset($arr[$category_id]))
             {
                return "";
             }
    
             foreach($arr[$category_id] AS $key => $cate)
             {
                 if ($cate['id'] == $default_category)
                 {
                     $txt = "                 }else{
                     $txt = "                 }
            
                 if ($level > 0)
                 {
                    $txt1 = ">" . str_repeat( "-", $level ) . " " . $cate['name'] . "\n";
                 }else{
                     $txt1 = ">" . $cate['name'] . "\n";
                 }
                 $val = $txt.$txt1;
                 echo $val;
                 self::Get_Category($key, $level + 1, $default_category);
             }
            
        }
        
        
        function getFlush($category_id = 0,$level = 0, $default_category = 0)
        {
            
            ob_start();

            self::Get_Category($category_id ,$level, $default_category);

            $out = ob_get_contents();

            ob_end_clean();
            return $out;
        }    
}
$id =$_GET['id'];
echo "";
$c = new cate();
//$c->Get_Category();
$ttt=  $c->getFlush($id,'0','3');
echo $ttt;
echo "";
?>

求两个日期的差数，例如2007-2-5 ~ 2007-3-6 的日期差数

方法一：

class Dtime

{

function get_days($date1, $date2)

{

   $time1 = strtotime($date1);

   $time2 = strtotime($date2);

   return ($time2-$time1)/86400;

}

}

$Dtime = new Dtime;

echo $Dtime->get_days('2007-2-5', '2007-3-6');

?>

方法二：

$temp = explode('-', '2007-2-5');

$time1 = mktime(0, 0, 0, $temp[1], $temp[2], $temp[0]);

$temp = explode('-', '2007-3-6');

$time2 = mktime(0, 0, 0, $temp[1], $temp[2], $temp[0]);

echo ($time2-$time1)/86400;

字符串“open_door” 转换成 “opendoor”、”make_by_id” 转换成 ”makebyid”

function changeStyle($str){
$arr = explode('_',$str);
$new_str = '';
foreach($arr as $v){
$new_str .= ucfirst($v);
}
return $new_str;
}
echo changeStyle('open_door')."
"; //OpenDoor
echo changeStyle('make_by_id'); //MakeById

要求写一段程序，实现以下数组$arr1转换成数组$arr2：

$arr1 = array (

       '0' => array ('fid' => 1, 'tid' => 1, 'name' =>'Name1' ),

       '1' => array ('fid' => 1, 'tid' => 2 , 'name' =>'Name2' ),

       '2' => array ('fid' => 1, 'tid' => 5 , 'name' =>'Name3' ),

       '3' => array ('fid' => 1, 'tid' => 7 , 'name' =>'Name4' ),

       '4' => array ('fid' => 3, 'tid' => 9, 'name' =>'Name5' )

);

$arr2 = array (

       '0' => array (

              '0' => array ( 'tid' => 1, 'name' => 'Name1'),

              '1' => array ( 'tid' => 2, 'name' => 'Name2'),

              '2' => array ( 'tid' => 5, 'name' => 'Name3'),

              '3' => array ( 'tid' => 7, 'name' => 'Name4')

),

       '1' => array (

              '0' => array ( 'tid' => 9, 'name' => 'Name5' )

)

);

实现代码如下：
$arr1 = array (

       '0' => array ('fid' => 1, 'tid' => 1, 'name' =>'Name1' ),

       '1' => array ('fid' => 1, 'tid' => 2 , 'name' =>'Name2' ),

       '2' => array ('fid' => 1, 'tid' => 5 , 'name' =>'Name3' ),

       '3' => array ('fid' => 1, 'tid' => 7 , 'name' =>'Name4' ),

       '4' => array ('fid' => 3, 'tid' => 9, 'name' =>'Name5' )

);
$arr2 = array();
$i = 0;
foreach($arr1 as $key=>$val)
{
unset($val['fid']);   //将键值为fid的元素释放（去掉）
$arr2[$i][] = $val;
if($key == 3)
   $i++;
}
echo '

';<br>print_r($arr2);<br>echo '<pre class="brush:php;toolbar:false">

//插入排序（一维数组）

function insert_sort($arr){

　$count = count($arr);

　for($i=1; $i

　　$tmp = $arr[$i];

　　$j = $i - 1;

　　while($arr[$j] > $tmp){

　　　$arr[$j+1] = $arr[$j];

　　　$arr[$j] = $tmp;

　　　$j--;

　　}

　return $arr;

//选择排序（一维数组）

function select_sort($arr){

　$count = count($arr);

　for($i=0; $i

　　$k = $i;

　　for($j=$i+1; $j

　　　if ($arr[$k] > $arr[$j])

　　　　$k = $j;

　　　if ($k != $i){

　　　　$tmp = $arr[$i];

　　　　$arr[$i] = $arr[$k];

　　　　$arr[$k] = $tmp;

　　　}

　　}

　return $arr;

//冒泡排序（一维数组）

function bubble_sort($array){

　$count = count($array);

　if ($count

　for($i=0; $i

　　for($j=$count-1; $j>$i; $j--){

　　　if ($array[$j]

　　　　$tmp = $array[$j];

　　　　$array[$j] = $array[$j-1];

　　　　$array[$j-1] = $tmp;

　　　}

　　}

　return $array;

//快速排序（一维数组）

function quick_sort($array){

　if (count($array)

　$key = $array[0];

　$left_arr = array();

　$right_arr = array();

　for ($i=1; $i

　　if ($array[$i]

　　　$left_arr[] = $array[$i];

　　else

　　　$right_arr[] = $array[$i];

　$left_arr = quick_sort($left_arr);

　$right_arr = quick_sort($right_arr);

　return array_merge($left_arr, array($key), $right_arr);