Home php教程 php手册 php 邮件发送类

php 邮件发送类

Jun 13, 2016 am 10:09 AM
class int php port server smtp var send kind mail

php 邮件发送类

class SMTP
{
    /**
     *  SMTP server port
     *  @var int
     */
    var $SMTP_PORT = 25;
   
    /**
     *  SMTP reply line ending
     *  @var string
     */
    var $CRLF = "rn";
   
    /**
     *  Sets whether debugging is turned on
     *  @var bool
     */
    var $do_debug;       # the level of debug to perform

    /**#@+
     * @access private
     */
    var $smtp_conn;      # the socket to the server
    var $error;          # error if any on the last call
    var $helo_rply;      # the reply the server sent to us for HELO
    /**#@-*/

    /**
     * Initialize the class so that the data is in a known state.
     * @access public
     * @return void
     */
    function SMTP() {
        $this->smtp_conn = 0;
        $this->error = null;
        $this->helo_rply = null;

        $this->do_debug = 0;
    }

    /*************************************************************
     *                    CONNECTION FUNCTIONS                  *
     ***********************************************************/

    /**
     * Connect to the server specified on the port specified.
     * If the port is not specified use the default SMTP_PORT.
     * If tval is specified then a connection will try and be
     * established with the server for that number of seconds.
     * If tval is not specified the default is 30 seconds to
     * try on the connection.
     *
     * SMTP CODE SUCCESS: 220
     * SMTP CODE FAILURE: 421
     * @access public
     * @return bool
     */
    function Connect($host,$port=0,$tval=30) {
        # set the error val to null so there is no confusion
        $this->error = null;

        # make sure we are __not__ connected
        if($this->connected()) {
            # ok we are connected! what should we do?
            # for now we will just give an error saying we
            # are already connected
            $this->error =
                array("error" => "Already connected to a server");
            return false;
        }

        if(empty($port)) {
            $port = $this->SMTP_PORT;
        }

        #connect to the smtp server
        $this->smtp_conn = fsockopen($host,    # the host of the server
                                     $port,    # the port to use
                                     $errno,   # error number if any
                                     $errstr,  # error message if any
                                     $tval);   # give up after ? secs
        # verify we connected properly
        if(empty($this->smtp_conn)) {
            $this->error = array("error" => "Failed to connect to server",
                                 "errno" => $errno,
                                 "errstr" => $errstr);
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": $errstr ($errno)" . $this->CRLF;
            }
            return false;
        }

        # sometimes the SMTP server takes a little longer to respond
        # so we will give it a longer timeout for the first read
        // Windows still does not have support for this timeout function
        if(substr(PHP_OS, 0, 3) != "WIN")
           socket_set_timeout($this->smtp_conn, $tval, 0);

        # get any announcement stuff
        $announce = $this->get_lines();

        # set the timeout  of any socket functions at 1/10 of a second
        //if(function_exists("socket_set_timeout"))
        //   socket_set_timeout($this->smtp_conn, 0, 100000);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $announce;
        }

        return true;
    }

    /**
     * Performs SMTP authentication.  Must be run after running the
     * Hello() method.  Returns true if successfully authenticated.
     * @access public
     * @return bool
     */
    function Authenticate($username, $password) {
        // Start authentication
        fputs($this->smtp_conn,"AUTH LOGIN" . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($code != 334) {
            $this->error =
                array("error" => "AUTH not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }

        // Send encoded username
        fputs($this->smtp_conn, base64_encode($username) . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($code != 334) {
            $this->error =
                array("error" => "Username not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }

        // Send encoded password
        fputs($this->smtp_conn, base64_encode($password) . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($code != 235) {
            $this->error =
                array("error" => "Password not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }

        return true;
    }

    /**
     * Returns true if connected to a server otherwise false
     * @access private
     * @return bool
     */
    function Connected() {
        if(!empty($this->smtp_conn)) {
            $sock_status = socket_get_status($this->smtp_conn);
            if($sock_status["eof"]) {
                # hmm this is an odd situation... the socket is
                # valid but we aren't connected anymore
                if($this->do_debug >= 1) {
                    echo "SMTP -> NOTICE:" . $this->CRLF .
                         "EOF caught while checking if connected";
                }
                $this->Close();
                return false;
            }
            return true; # everything looks good
        }
        return false;
    }

    /**
     * Closes the socket and cleans up the state of the class.
     * It is not considered good to use this function without
     * first trying to use QUIT.
     * @access public
     * @return void
     */
    function Close() {
        $this->error = null; # so there is no confusion
        $this->helo_rply = null;
        if(!empty($this->smtp_conn)) {
            # close the connection and cleanup
            fclose($this->smtp_conn);
            $this->smtp_conn = 0;
        }
    }


    /***************************************************************
     *                        SMTP COMMANDS                       *
     *************************************************************/

    /**
     * Issues a data command and sends the msg_data to the server
     * finializing the mail transaction. $msg_data is the message
     * that is to be send with the headers. Each header needs to be
     * on a single line followed by a with the message headers
     * and the message body being seperated by and additional .
     *
     * Implements rfc 821: DATA
     *
     * SMTP CODE INTERMEDIATE: 354
     *     [data]
     *     .
     *     SMTP CODE SUCCESS: 250
     *     SMTP CODE FAILURE: 552,554,451,452
     * SMTP CODE FAILURE: 451,554
     * SMTP CODE ERROR  : 500,501,503,421
     * @access public
     * @return bool
     */
    function Data($msg_data) {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Data() without being connected");
            return false;
        }

        fputs($this->smtp_conn,"DATA" . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 354) {
            $this->error =
                array("error" => "DATA command not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }

        # the server is ready to accept data!
        # according to rfc 821 we should not send more than 1000
        # including the CRLF
        # characters on a single line so we will break the data up
        # into lines by r and/or n then if needed we will break
        # each of those into smaller lines to fit within the limit.
        # in addition we will be looking for lines that start with
        # a period '.' and append and additional period '.' to that
        # line. NOTE: this does not count towards are limit.

        # normalize the line breaks so we know the explode works
        $msg_data = str_replace("rn","n",$msg_data);
        $msg_data = str_replace("r","n",$msg_data);
        $lines = explode("n",$msg_data);

        # we need to find a good way to determine is headers are
        # in the msg_data or if it is a straight msg body
        # currently I'm assuming rfc 822 definitions of msg headers
        # and if the first field of the first line (':' sperated)
        # does not contain a space then it _should_ be a header
        # and we can process all lines before a blank "" line as
        # headers.
        $field = substr($lines[0],0,strpos($lines[0],":"));
        $in_headers = false;
        if(!empty($field) && !strstr($field," ")) {
            $in_headers = true;
        }

        $max_line_length = 998; # used below; set here for ease in change

        while(list(,$line) = @each($lines)) {
            $lines_out = null;
            if($line == "" && $in_headers) {
                $in_headers = false;
            }
            # ok we need to break this line up into several
            # smaller lines
            while(strlen($line) > $max_line_length) {
                $pos = strrpos(substr($line,0,$max_line_length)," ");
                $lines_out[] = substr($line,0,$pos);
                $line = substr($line,$pos + 1);
                # if we are processing headers we need to
                # add a LWSP-char to the front of the new line
                # rfc 822 on long msg headers
                if($in_headers) {
                    $line = "t" . $line;
                }
            }
            $lines_out[] = $line;

            # now send the lines to the server
            while(list(,$line_out) = @each($lines_out)) {
                if(strlen($line_out) > 0)
                {
                    if(substr($line_out, 0, 1) == ".") {
                        $line_out = "." . $line_out;
                    }
                }
                fputs($this->smtp_conn,$line_out . $this->CRLF);
            }
        }

        # ok all the message data has been sent so lets get this
        # over with aleady
        fputs($this->smtp_conn, $this->CRLF . "." . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250) {
            $this->error =
                array("error" => "DATA not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }
        return true;
    }

    /**
     * Expand takes the name and asks the server to list all the
     * people who are members of the _list_. Expand will return
     * back and array of the result or false if an error occurs.
     * Each value in the array returned has the format of:
     *     [ ]
     * The definition of is defined in rfc 821
     *
     * Implements rfc 821: EXPN
     *
     * SMTP CODE SUCCESS: 250
     * SMTP CODE FAILURE: 550
     * SMTP CODE ERROR  : 500,501,502,504,421
     * @access public
     * @return string array
     */
    function Expand($name) {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Expand() without being connected");
            return false;
        }

        fputs($this->smtp_conn,"EXPN " . $name . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250) {
            $this->error =
                array("error" => "EXPN not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }

        # parse the reply and place in our array to return to user
        $entries = explode($this->CRLF,$rply);
        while(list(,$l) = @each($entries)) {
            $list[] = substr($l,4);
        }

        return $list;
    }

    /**
     * Sends the HELO command to the smtp server.
     * This makes sure that we and the server are in
     * the same known state.
     *
     * Implements from rfc 821: HELO
     *
     * SMTP CODE SUCCESS: 250
     * SMTP CODE ERROR  : 500, 501, 504, 421
     * @access public
     * @return bool
     */
    function Hello($host="") {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Hello() without being connected");
            return false;
        }

        # if a hostname for the HELO wasn't specified determine
        # a suitable one to send
        if(empty($host)) {
            # we need to determine some sort of appopiate default
            # to send to the server
            $host = "localhost";
        }

        // Send extended hello first (RFC 2821)
        if(!$this->SendHello("EHLO", $host))
        {
            if(!$this->SendHello("HELO", $host))
                return false;
        }

        return true;
    }

    /**
     * Sends a HELO/EHLO command.
     * @access private
     * @return bool
     */
    function SendHello($hello, $host) {
        fputs($this->smtp_conn, $hello . " " . $host . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER: " . $this->CRLF . $rply;
        }

        if($code != 250) {
            $this->error =
                array("error" => $hello . " not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }

        $this->helo_rply = $rply;
       
        return true;
    }

    /**
     * Gets help information on the keyword specified. If the keyword
     * is not specified then returns generic help, ussually contianing
     * A list of keywords that help is available on. This function
     * returns the results back to the user. It is up to the user to
     * handle the returned data. If an error occurs then false is
     * returned with $this->error set appropiately.
     *
     * Implements rfc 821: HELP [ ]
     *
     * SMTP CODE SUCCESS: 211,214
     * SMTP CODE ERROR  : 500,501,502,504,421
     * @access public
     * @return string
     */
    function Help($keyword="") {
        $this->error = null; # to avoid confusion

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Help() without being connected");
            return false;
        }

        $extra = "";
        if(!empty($keyword)) {
            $extra = " " . $keyword;
        }

        fputs($this->smtp_conn,"HELP" . $extra . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 211 && $code != 214) {
            $this->error =
                array("error" => "HELP not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }

        return $rply;
    }

    /**
     * Starts a mail transaction from the email address specified in
     * $from. Returns true if successful or false otherwise. If True
     * the mail transaction is started and then one or more Recipient
     * commands may be called followed by a Data command.
     *
     * Implements rfc 821: MAIL FROM:
     *
     * SMTP CODE SUCCESS: 250
     * SMTP CODE SUCCESS: 552,451,452
     * SMTP CODE SUCCESS: 500,501,421
     * @access public
     * @return bool
     */
    function Mail($from) {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Mail() without being connected");
                 
            return false;
        }
        fputs($this->smtp_conn,"MAIL FROM:" . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);
     
        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250) {
            $this->error =
                array("error" => "MAIL not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }
        return true;
    }

    /**
     * Sends the command NOOP to the SMTP server.
     *
     * Implements from rfc 821: NOOP
     *
     * SMTP CODE SUCCESS: 250
     * SMTP CODE ERROR  : 500, 421
     * @access public
     * @return bool
     */
    function Noop() {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Noop() without being connected");
            return false;
        }

        fputs($this->smtp_conn,"NOOP" . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250) {
            $this->error =
                array("error" => "NOOP not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }
        return true;
    }

    /**
     * Sends the quit command to the server and then closes the socket
     * if there is no error or the $close_on_error argument is true.
     *
     * Implements from rfc 821: QUIT
     *
     * SMTP CODE SUCCESS: 221
     * SMTP CODE ERROR  : 500
     * @access public
     * @return bool
     */
    function Quit($close_on_error=true) {
        $this->error = null; # so there is no confusion

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Quit() without being connected");
            return false;
        }

        # send the quit command to the server
        fputs($this->smtp_conn,"quit" . $this->CRLF);

        # get any good-bye messages
        $byemsg = $this->get_lines();

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $byemsg;
        }

        $rval = true;
        $e = null;

        $code = substr($byemsg,0,3);
        if($code != 221) {
            # use e as a tmp var cause Close will overwrite $this->error
            $e = array("error" => "SMTP server rejected quit command",
                       "smtp_code" => $code,
                       "smtp_rply" => substr($byemsg,4));
            $rval = false;
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $e["error"] . ": " .
                         $byemsg . $this->CRLF;
            }
        }

        if(empty($e) || $close_on_error) {
            $this->Close();
        }

        return $rval;
    }

    /**
     * Sends the command RCPT to the SMTP server with the TO: argument of $to.
     * Returns true if the recipient was accepted false if it was rejected.
     *
     * Implements from rfc 821: RCPT TO:
     *
     * SMTP CODE SUCCESS: 250,251
     * SMTP CODE FAILURE: 550,551,552,553,450,451,452
     * SMTP CODE ERROR  : 500,501,503,421
     * @access public
     * @return bool
     */
    function Recipient($to) {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Recipient() without being connected");
            return false;
        }

        fputs($this->smtp_conn,"RCPT TO:" . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250 && $code != 251) {
            $this->error =
                array("error" => "RCPT not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }
        return true;
    }

    /**
     * Sends the RSET command to abort and transaction that is
     * currently in progress. Returns true if successful false
     * otherwise.
     *
     * Implements rfc 821: RSET
     *
     * SMTP CODE SUCCESS: 250
     * SMTP CODE ERROR  : 500,501,504,421
     * @access public
     * @return bool
     */
    function Reset() {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Reset() without being connected");
            return false;
        }

        fputs($this->smtp_conn,"RSET" . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250) {
            $this->error =
                array("error" => "RSET failed",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }

        return true;
    }

    /**
     * Starts a mail transaction from the email address specified in
     * $from. Returns true if successful or false otherwise. If True
     * the mail transaction is started and then one or more Recipient
     * commands may be called followed by a Data command. This command
     * will send the message to the users terminal if they are logged
     * in.
     *
     * Implements rfc 821: SEND FROM:
     *
     * SMTP CODE SUCCESS: 250
     * SMTP CODE SUCCESS: 552,451,452
     * SMTP CODE SUCCESS: 500,501,502,421
     * @access public
     * @return bool
     */
    function Send($from) {
        $this->error = null; # so no confusion is caused

        if(!$this->connected()) {
            $this->error = array(
                    "error" => "Called Send() without being connected");
            return false;
        }

        fputs($this->smtp_conn,"SEND FROM:" . $from . $this->CRLF);

        $rply = $this->get_lines();
        $code = substr($rply,0,3);

        if($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }

        if($code != 250) {
            $this->error =
                array("error" => "SEND not accepted from server",
                      "smtp_code" => $code,
                      "smtp_msg" => substr($rply,4));
            if($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] .
                         ": " . $rply . $this->CRLF;
            }
            return false;
        }
        return true;
    }

    /**
     * Starts a mail transaction from the email address specified in
     * $from. Returns true if successful or false otherwise. If True
     * the mail transaction is started and then one or more Recipient
     * commands may be called followed by a Data command. This command
     * will send the message to the users terminal if they are logged
     * in and send them an email.
     *
     * Implements rfc 821: SAML FROM:
     *
     * SMTP CODE SUCCESS: 250
     * SMTP CODE SUCCESS: 552,451,452
     * SMTP CODE SUCCESS: 500,501,502,421
     * @access public
     * @return bool
  &nbs

Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

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

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Hot Topics

Java Tutorial
1662
14
PHP Tutorial
1262
29
C# Tutorial
1235
24
How do you parse and process HTML/XML in PHP? How do you parse and process HTML/XML in PHP? Feb 07, 2025 am 11:57 AM

This tutorial demonstrates how to efficiently process XML documents using PHP. XML (eXtensible Markup Language) is a versatile text-based markup language designed for both human readability and machine parsing. It's commonly used for data storage an

Explain JSON Web Tokens (JWT) and their use case in PHP APIs. Explain JSON Web Tokens (JWT) and their use case in PHP APIs. Apr 05, 2025 am 12:04 AM

JWT is an open standard based on JSON, used to securely transmit information between parties, mainly for identity authentication and information exchange. 1. JWT consists of three parts: Header, Payload and Signature. 2. The working principle of JWT includes three steps: generating JWT, verifying JWT and parsing Payload. 3. When using JWT for authentication in PHP, JWT can be generated and verified, and user role and permission information can be included in advanced usage. 4. Common errors include signature verification failure, token expiration, and payload oversized. Debugging skills include using debugging tools and logging. 5. Performance optimization and best practices include using appropriate signature algorithms, setting validity periods reasonably,

Explain late static binding in PHP (static::). Explain late static binding in PHP (static::). Apr 03, 2025 am 12:04 AM

Static binding (static::) implements late static binding (LSB) in PHP, allowing calling classes to be referenced in static contexts rather than defining classes. 1) The parsing process is performed at runtime, 2) Look up the call class in the inheritance relationship, 3) It may bring performance overhead.

PHP Program to Count Vowels in a String PHP Program to Count Vowels in a String Feb 07, 2025 pm 12:12 PM

A string is a sequence of characters, including letters, numbers, and symbols. This tutorial will learn how to calculate the number of vowels in a given string in PHP using different methods. The vowels in English are a, e, i, o, u, and they can be uppercase or lowercase. What is a vowel? Vowels are alphabetic characters that represent a specific pronunciation. There are five vowels in English, including uppercase and lowercase: a, e, i, o, u Example 1 Input: String = "Tutorialspoint" Output: 6 explain The vowels in the string "Tutorialspoint" are u, o, i, a, o, i. There are 6 yuan in total

What are PHP magic methods (__construct, __destruct, __call, __get, __set, etc.) and provide use cases? What are PHP magic methods (__construct, __destruct, __call, __get, __set, etc.) and provide use cases? Apr 03, 2025 am 12:03 AM

What are the magic methods of PHP? PHP's magic methods include: 1.\_\_construct, used to initialize objects; 2.\_\_destruct, used to clean up resources; 3.\_\_call, handle non-existent method calls; 4.\_\_get, implement dynamic attribute access; 5.\_\_set, implement dynamic attribute settings. These methods are automatically called in certain situations, improving code flexibility and efficiency.

PHP and Python: Comparing Two Popular Programming Languages PHP and Python: Comparing Two Popular Programming Languages Apr 14, 2025 am 12:13 AM

PHP and Python each have their own advantages, and choose according to project requirements. 1.PHP is suitable for web development, especially for rapid development and maintenance of websites. 2. Python is suitable for data science, machine learning and artificial intelligence, with concise syntax and suitable for beginners.

PHP in Action: Real-World Examples and Applications PHP in Action: Real-World Examples and Applications Apr 14, 2025 am 12:19 AM

PHP is widely used in e-commerce, content management systems and API development. 1) E-commerce: used for shopping cart function and payment processing. 2) Content management system: used for dynamic content generation and user management. 3) API development: used for RESTful API development and API security. Through performance optimization and best practices, the efficiency and maintainability of PHP applications are improved.

PHP: A Key Language for Web Development PHP: A Key Language for Web Development Apr 13, 2025 am 12:08 AM

PHP is a scripting language widely used on the server side, especially suitable for web development. 1.PHP can embed HTML, process HTTP requests and responses, and supports a variety of databases. 2.PHP is used to generate dynamic web content, process form data, access databases, etc., with strong community support and open source resources. 3. PHP is an interpreted language, and the execution process includes lexical analysis, grammatical analysis, compilation and execution. 4.PHP can be combined with MySQL for advanced applications such as user registration systems. 5. When debugging PHP, you can use functions such as error_reporting() and var_dump(). 6. Optimize PHP code to use caching mechanisms, optimize database queries and use built-in functions. 7

See all articles