PHP database connection version1.1

This month has really been a bit of a mess .... Keep reviewing , Reading a book .. Finally, I have finished the exam today 2 Coe . Can let me write a blog well .. Some time ago PHP I learned more about the lesson design , In what our teachers say php Some optimizations have been made in connection with the database . I sent the first version some time ago , The coupling is a little high . Asked the teacher , I imitate java I also wrote a database connection pool ... Compare the basic connection mode .

The first is XML file .. You only need to modify the corresponding ,DB_HOST,DB_USER,DB_PWD that will do .

<?xml version="1.0" encoding="UTF-8"?>

<database>

<DB_HOST>localhost </DB_HOST>

<DB_USER>root </DB_USER>

<DB_PWD>root </DB_PWD>

<DB_NAME>php_car </DB_NAME>

</database>

This is the file that mainly controls the connection ...

<?php

/**

* Created by PhpStorm.

* User: gjt

* Date: 2018/1/5

* Time: 11:07

*/

/**

* header Set character set

* define Constant , Non modifiable

*/

header( "Content-Type:text/html;charset=utf-8");

$file="DataBase.XML";

$con=file_get_contents( $file);

/**

* XML Document labels

*/

$xmlTag=array(

"DB_HOST",

"DB_USER",

"DB_PWD",

"DB_NAME"

);

$arr=array();

/**

* Traversal tag

*/

foreach( $xmlTagas$x){

preg_match_all( "/<".$x.">.*<\/".$x.">/", $con, $temp);

$arr[]=$temp[0];

}

$data=array();

foreach( $arras$key=> $value) {

foreach( $valueas$k=> $v) {

$a= explode( $xmlTag[$key].'>', $v);

$v= substr( $a[1], 0, strlen( $a[1]) -2);

$data[$k][$xmlTag[$key]]=$v;

}

}

echo'<pre>';

/*print_r($data[0]);*/

define( 'DB_HOST', $data[0][$xmlTag[0]]);

define( 'DB_USER', $data[0][$xmlTag[1]]);

define( 'DB_PWD', $data[0][$xmlTag[2]]);

define( 'DB_NAME', $data[0][$xmlTag[3]]); // You need to change it to your own database name

global$conn;

/**

* Connect mysql

*/

$conn=@mysqli_connect( DB_HOST, DB_USER, DB_PWD) ordie( " The connection fails ".mysqli_error( $conn));

/**

* Select the specified database , Character set

*/

mysqli_select_db( $conn, DB_NAME) ordie( " Database error ".mysqli_error( $conn));

echo" Successful connection ";

/*mysqli_query($conn, "SET NAMES UTF-8");*/

$file Fill in the name of the document . Created .xml File name of the file .

After that ...

Use this sentence .

require"config.php";

global$conn;

You can establish a database connection ...

I can write another file here , Define some default methods .. Minimize the amount of code ..

forehead .............. That's it .... It is estimated that there is not much time to toss about in the future php 了 .. Do it well java Slightly ....