细说php读书笔记,深入理解PHP读书笔记

第一章  高级PHP技巧

1.1 多维数组排序

1.1.1 多维数组排序

$a&＃61;array(

array(&＃39;key1&＃39;&＃61;>940,&＃39;key2&＃39;&＃61;>&＃39;blah&＃39;),

array(&＃39;key1&＃39;&＃61;>23,&＃39;key2&＃39;&＃61;>&＃39;this&＃39;),

array(&＃39;key1&＃39;&＃61;>894,&＃39;key2&＃39;&＃61;>&＃39;that&＃39;)

);

print_r($a);

function asc_number_sort($x,$y){

if($x[&＃39;key1&＃39;]>$y[&＃39;key1&＃39;]){

return true;

}elseif($x[&＃39;key1&＃39;]

return false;

}else{

return 0;

}

}

usort($a,&＃39;asc_number_sort&＃39;);

$a&＃61;array(

array(&＃39;key1&＃39;&＃61;>940,&＃39;key2&＃39;&＃61;>&＃39;blah&＃39;),

array(&＃39;key1&＃39;&＃61;>23,&＃39;key2&＃39;&＃61;>&＃39;this&＃39;),

array(&＃39;key1&＃39;&＃61;>894,&＃39;key2&＃39;&＃61;>&＃39;that&＃39;)

);

function string_sort($x,$y){

return strcasecmp($x[&＃39;key2&＃39;],$y[&＃39;key2&＃39;]);

}

usort($a,&＃39;string_sort&＃39;);

$students&＃61;array(

256&＃61;>array(&＃39;name&＃39;&＃61;>&＃39;John&＃39;,&＃39;grade&＃39;&＃61;>98.5),

2&＃61;> array(&＃39;name&＃39;&＃61;>&＃39;Vance&＃39;,&＃39;grade&＃39;&＃61;>85.1),

9&＃61;> array(&＃39;name&＃39;&＃61;>&＃39;Stephen&＃39;,&＃39;grade&＃39;&＃61;>94.0),

364&＃61;>array(&＃39;name&＃39;&＃61;>&＃39;Steve&＃39;,&＃39;grade&＃39;&＃61;>85.1),

68&＃61;> array(&＃39;name&＃39;&＃61;>&＃39;Rob&＃39;,&＃39;grade&＃39;&＃61;>74.6)

);

function name_sort($x,$y){

return strcasecmp($x[&＃39;name&＃39;],$y[&＃39;name&＃39;]);

}

function grade_sort($x,$y){

return ($x[&＃39;grade&＃39;]

}

echo &＃39;

Array As Is

&＃39;.print_r($students,1).&＃39;&＃39;;

uasort($students,&＃39;name_sort&＃39;);

echo &＃39;

Array Sorted By Name

&＃39;.print_r($students,1).&＃39;&＃39;;

uasort($students,&＃39;grade_sort&＃39;);

echo &＃39;

Array Sorted By Grade

&＃39;.print_r($students,1).&＃39;&＃39;;

1.1.2 数据库驱动的数组

$dbc&＃61;mysqli_connect(&＃39;localhost&＃39;,&＃39;root&＃39;,&＃39;&＃39;,&＃39;php&＃39;);

if(($_SERVER[&＃39;REQUEST_METHOD&＃39;]&＃61;&＃61;&＃39;POST&＃39;)&& !empty($_POST[&＃39;task&＃39;])){

if(isset($_POST[&＃39;parent_id&＃39;])&& filter_var($_POST[&＃39;parent_id&＃39;],FILTER_VALIDATE_INT,array(&＃39;min_rang&＃39;&＃61;>1))){

$parent_id&＃61;$_POST[&＃39;parent_id&＃39;];

}else{

$parent_id&＃61;0;

}

$task&＃61;mysqli_real_escape_string($dbc,strip_tags($_POST[&＃39;task&＃39;]));

$q&＃61;"insert into tasks(parent_id,task) values($parent_id,&＃39;$task&＃39;)";

$r&＃61;mysqli_query($dbc,$q);

if(mysqli_affected_rows($dbc)&＃61;&＃61;1){

echo &＃39;

The task has been added

}else{

echo &＃39;

The task chould not be added!

}

}

echo &＃39;

Add a Task

Task:

Parent Task:None&＃39;;

$q&＃61;&＃39;select task_id,parent_id ,task from tasks where date_completed&＃61;"0000-00-00 00:00:00" order by date_added ASC&＃39;;

$r&＃61;mysqli_query($dbc,$q);

$task&＃61;array();

while(list($task_id,$parent_id,$task)&＃61;mysqli_fetch_array($r,MYSQL_NUM)){

echo "$task\n";

$tasks[]&＃61;array(&＃39;task_id&＃39;&＃61;>$task_id,&＃39;parent_id&＃39;&＃61;>$parent_id,&＃39;task&＃39;&＃61;>$task);

}

echo &＃39;

&＃39;;

function parent_sort($x,$y){

return ($x[&＃39;parent_id&＃39;]>$y[&＃39;parent_id&＃39;]);

}

usort($tasks,&＃39;parent_sort&＃39;);

echo &＃39;

Current To-Do List

• &＃39;;

foreach($tasks as $task){

echo "

}

echo &＃39;

1.2 高级函数定义

递归函数

静态变量

以引用方式接收值

匿名函数

1.2.1 递归函数

递归 recursion 就是函数自己调用自己的行为。

global $tasks;

echo &＃39;

1. &＃39;;

foreach($parent as $task_id&＃61;>$todo){

echo "

if(isset($tasks[$task_id])){

make_list($tasks[$task_id]);

}

echo "

}

echo "

}

$dbc&＃61;mysqli_connect(&＃39;localhost&＃39;,&＃39;root&＃39;,&＃39;&＃39;,&＃39;php&＃39;);

$q&＃61;&＃39;select task_id,parent_id,task from tasks where date_completed&＃61;"0000-00-00 00:00:00" order by parent_id,date_added asc&＃39;;

$r&＃61;mysqli_query($dbc,$q);

$tasks&＃61;array();

while(list($task_id,$parent_id,$task)&＃61;mysqli_fetch_array($r,MYSQLI_NUM)){

$tasks[$parent_id][$task_id]&＃61;$task;

}

echo &＃39;

&＃39;.print_r($tasks,1).&＃39;&＃39;;

make_list($tasks[0]);