PHP regular expressions, arrays, functions

<?php
Regular expressions
Slash stands for delimiters
/* $b = "ab2cde123fg1h";
$a = "/\d/";
Echo preg_replace ($a, "|", $b);//replace string B with regular expression a

Var_dump (Preg_split ($a, $b));//split B according to regular expression a
$shuzu = Array ();
Preg_match ($a, $b, $shuzu);//Match satisfies the first data in the regular expression
Var_dump ($shuzu);
Preg_match_all ($a, $b, $shuzu); *///matches All

Array
Defined
$a = array (1,2,3,4,5);//define Array mode 1
Assignment definition
$b [0] = 5;
$b [1] = 6;
Classification
1. Indexed arrays
$a = array (1,2,3,4,5);
2. Associative arrays
$b = Array ("One" =>5, "=>10");
echo $b ["one"];
PHP Array Features: Store any type of data, the length can be changed


$a 1 = array ("AA", "BB", "CC");
$a = Array ("A" =>1, "B" =>2, "C" =>3, "D" =>4, "E" =>5,);
For loop traversal, cannot traverse associative array
/*for ($i =0; $i <count ($a); $i + +)
{
echo $a [$i]. " <br> ";} */

foreach traversal
1.foreach ($a as $value)
/*{
echo $value. " <br> ";}
*/

2.foreach ($a as $key = $value)
/*{
echo $key. " --". $value." <br> ";}
*/

3.each function
Var_dump (each ($a));//Returns the $key and $value inside the array, each pointing to the next

4.list () function
List ($a, $b, $c) = $a 1;//assigns the values inside the array to the variables in the list
echo $a;

5.each and List traversal arrays
/*while (List ($key, $value) =each ($a))
{
Each "($key)-($value) <br>";
}*/
6. Pointers
Var_dump (current ($a 1));//Take the value of the position pointed to by the present pointer
Echo key ($a 1);//key that points to the position of the current pointer
Next ($a 1);
Echo key ($a 1);//move the pointer downwards
Prev ($a 1);//Raise the pointer upward
End ($a 1);//Adjust the pointer to the last
Reset ($a 1);//Adjust the pointer to the first
/*do
{
echo key ($a). " --". current ($a);}
while (next ($a)) */
Print_r ();

In_array ("AA", $a);//Judging if there is no such value
Array_reverse ($a);//Flip An array
Count ($a);//Returns the number of array elements
Array_unique ($a); Array de-weight, output new array, index number problem
Array_values ($a);//re-index
Unset ();//delete the element in the array and delete the index number
Array_merge ($a, $a 1); Merging arrays
Array_push ($a, "DD"); Append elements to an array

Two-dimensional arrays
/* $a = array (
Array (+/-),
Array (4,5,6,),
Array (7,8,9)
);

Var_dump ($a); * *

/* $a = array (
Array ("n001", "Han"),
Array ("n002", "Miao"),
Array ("n003", "Hui"),
Array ("n004", "Uighur"),
);
Displays the contents of the array as a drop-down list
echo "<select>";
foreach ($a as $value)
{
echo "<option value= ' {$value [0]} ' > ($value [1]) </option>";}
echo "</select>"; * *

Display the contents of a two-dimensional array as a single table
$a = Array (
Array ("P001", "Zhang San", "Male", "Han"),
Array ("P002", ' John Doe ', ' Male ', "Miao"),
Array ("P003", ' Zhang Hong ', ' female ', "Hui"),
Array ("P004", ' Zhaowen ', ' female ', "Uighur"),
);
echo "<table width= ' 100% ' border= ' 1 ' cellpadding= ' 0 ' cellspacing= ' 0 ' >";
echo "<tr height= ' ><td> codes </td>><td> names </td>><td> gender </td>> <td> Han </td></tr> ";
echo "<tr><td>{$a [0][0]}</td><td>{$a [i][1]}</td><td>{$a [i][2]}</td> <td>{$a [i][3]}</td></tr> ";
for ($i =0; $i <count ($a); $i + +)
{
echo "<tr><td>{$a [$i][0]}</td><td>{$a [$i][1]}</td><td>{$a [$i][2]}</td ><td>{$a [$i][3]}</td></tr>];}

echo "</table>";


?>

PHP regular expressions, arrays, functions