Mysql class written by myself_PHP tutorial
---------- php debug ----------
Server=localhost;DataBase=mysql;UserID=root;PassWord=123456
resource(5) of type (mysql result)
Output completed (1 sec consumed) - Normal Termination
class DBCLS
{
//debug 调试开关
var $debug = true;
//debuginfo 错误信息,调试信息
var $debuginfo = "debug informations:
";
//db_server MySQL主机地址
var $db_server;
//db_name 数据库名
var $db_name;
//db_user 数据库用户名
var $db_user;
//db_passwd 密码
var $db_passwd;
//db_links 数据库连接
var $db_link;
//db_query_sql SQL语句
var $db_query_sql = "show tables";
//db_recordset 结果集,记录集
var $db_recordset;
//ready 就绪开关
var $conntstr_ready = false;
var $link_ready = false;
var $db_ready = false;
//set or return Connection String 返回,或者设定连接字符串
function connection_string($connstr="")
{
if("" == $connstr)
{
//如果没有参数传入,返回已有的连接字符
return "Server=".$this->db_server.";DataBase=".$this->db_name.";UserID=".$this->db_user.";PassWord=".$this->db_passwd;
}
else
{
//否则,解析连接字符,初始化变量
preg_match_all("|([a-zA-Z0-9]*)=([a-zA-Z0-9]*);*|", $connstr, $tmparr, PREG_PATTERN_ORDER);
$this->db_server = (strtolower($tmparr[1][0]) == "server")?$tmparr[2][0]:"";
$this->db_name = (strtolower($tmparr[1][1]) == "database")?$tmparr[2][1]:"";
$this->db_user = (strtolower($tmparr[1][2]) == "userid")?$tmparr[2][2]:"";
$this->db_passwd = (strtolower($tmparr[1][3]) == "password")?$tmparr[2][3]:"";
//var_dump($tmparr);
if("" == $this->db_server or "" == $this->db_name or "" == $this->db_user or "" == $this->db_passwd)
$this->conntstr_ready = false; //如果有其中一个以上变量被赋以空字符串"",准备未就绪
else
$this->conntstr_ready = true;
return $this->conntstr_ready;
}
}
//连接数据库,返回连接对象
function connect()
{
if(!$this->conntstr_ready)
{
if($this->debug){$this->debuginfo .= "连接字符串无效!
";}
return $this->link_ready;
}
if($this->db_link = @mysql_connect($this->db_server, $this->db_user, $this->db_passwd))
{
$this->link_ready = true;
return $this->link_ready;
}
}
//选择数据库
function select($db = "")
{
if(!$this->db_link)
{
if($this->debug){$this->debuginfo .= "没有可用的数据库连接!
";}
$this->db_ready = false;
}
if("" == $db)
{
if(mysql_select_db($this->db_name))
$this->db_ready = true;
}
if(mysql_select_db($this->db_name = $db))
$this->db_ready = true;
return $this->db_ready;
}
//执行查询
function execute($SQL = "")
{
if("" != $SQL)
{
$this->db_query_sql = $SQL;
//if($this->debug){$this->debuginfo .= "SQL is null!
";}
//return false;
}
if("" == $this->db_query_sql)
{
if($this->debug){$this->debuginfo .= "SQL is null!
";}
return false;
}
$this->db_recordset = mysql_query($this->db_query_sql);
return true;
}
}
$dbmy = new DBCLS(); //创建一个DBCLS对象
if(!$dbmy->connection_string("Server=localhost;DataBase=mysql;UserID=root;PassWord=123456"))//初始化DBCLS对象dbmy
print $dbmy->debuginfo; //初始化失败,输出错误信息
else
print $dbmy->connection_string(); //Initialization successful, output connection string
print "
";
if(!($dbmy->connect()) or !($dbmy->select())) //If connecting to the database or selecting the database fails
print $dbmy->debuginfo; //Output error message
//$dbmy->db_query_sql = "select * from user";
if($dbmy->execute()) //Execute query command
{ No error
var_dump($dbmy->db_recordset);//Output the returned result set
}
?>
Output information:
---------- php debug ----------
Server=localhost;DataBase=mysql;UserID=root;PassWord=123456
resource(5) of type (mysql result)
Output completed (1 sec consumed) - Normal Termination

What’s still popular is the ease of use, flexibility and a strong ecosystem. 1) Ease of use and simple syntax make it the first choice for beginners. 2) Closely integrated with web development, excellent interaction with HTTP requests and database. 3) The huge ecosystem provides a wealth of tools and libraries. 4) Active community and open source nature adapts them to new needs and technology trends.

PHP and Python are both high-level programming languages that are widely used in web development, data processing and automation tasks. 1.PHP is often used to build dynamic websites and content management systems, while Python is often used to build web frameworks and data science. 2.PHP uses echo to output content, Python uses print. 3. Both support object-oriented programming, but the syntax and keywords are different. 4. PHP supports weak type conversion, while Python is more stringent. 5. PHP performance optimization includes using OPcache and asynchronous programming, while Python uses cProfile and asynchronous programming.

PHP is mainly procedural programming, but also supports object-oriented programming (OOP); Python supports a variety of paradigms, including OOP, functional and procedural programming. PHP is suitable for web development, and Python is suitable for a variety of applications such as data analysis and machine learning.

PHP originated in 1994 and was developed by RasmusLerdorf. It was originally used to track website visitors and gradually evolved into a server-side scripting language and was widely used in web development. Python was developed by Guidovan Rossum in the late 1980s and was first released in 1991. It emphasizes code readability and simplicity, and is suitable for scientific computing, data analysis and other fields.

PHP is suitable for web development and rapid prototyping, and Python is suitable for data science and machine learning. 1.PHP is used for dynamic web development, with simple syntax and suitable for rapid development. 2. Python has concise syntax, is suitable for multiple fields, and has a strong library ecosystem.

PHP remains important in the modernization process because it supports a large number of websites and applications and adapts to development needs through frameworks. 1.PHP7 improves performance and introduces new features. 2. Modern frameworks such as Laravel, Symfony and CodeIgniter simplify development and improve code quality. 3. Performance optimization and best practices further improve application efficiency.

PHPhassignificantlyimpactedwebdevelopmentandextendsbeyondit.1)ItpowersmajorplatformslikeWordPressandexcelsindatabaseinteractions.2)PHP'sadaptabilityallowsittoscaleforlargeapplicationsusingframeworkslikeLaravel.3)Beyondweb,PHPisusedincommand-linescrip

PHP type prompts to improve code quality and readability. 1) Scalar type tips: Since PHP7.0, basic data types are allowed to be specified in function parameters, such as int, float, etc. 2) Return type prompt: Ensure the consistency of the function return value type. 3) Union type prompt: Since PHP8.0, multiple types are allowed to be specified in function parameters or return values. 4) Nullable type prompt: Allows to include null values and handle functions that may return null values.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

DVWA
Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software

VSCode Windows 64-bit Download
A free and powerful IDE editor launched by Microsoft

SublimeText3 Mac version
God-level code editing software (SublimeText3)

SAP NetWeaver Server Adapter for Eclipse
Integrate Eclipse with SAP NetWeaver application server.

Dreamweaver Mac version
Visual web development tools