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PHP全栈学习笔记13

PHP全栈学习笔记13

作者: 梅先森森森森森森 | 来源:发表于2019-10-23 12:06 被阅读0次
    image

    php与ajax技术

    web2.0的到来,ajax逐渐成为主流,什么是ajax,ajax的开发模式,优点,使用技术。(ajax概述,ajax使用的技术,需要注意的 问题,在PHP应用ajax技术的应用)

    什么是ajax,ajax的开发模式,优点。

    ajax是由jesse james garrett创建的,是asynchronous javascript and xml,异步javascript和xml技术,ajax并不是一门新的语言或技术,它是javascript,xml,css,dom等多种技术的组合,可以实现客户端的异步请求操作,可以在不刷新页面下与服务器进行通信,从而减少了用户的等待时间。

    ajax开发模式:
    浏览器(客户端) http传输,http请求, web服务器 数据存储,后端处理,继承系统,服务器端。

    客户端(浏览器)JavaScript调用,ajax引擎 http请求,http传输, web和xml服务器,数据存储,后端处理,继承系统(服务端)。

    优点:减轻服务器的负担,可以把部分由服务器负担的工作转移到客户端上,无刷新更新页面,可以调用xml等外部数据,基于标准化的并被广泛支持的技术。

    JavaScript是一种在web页面中添加动态脚本代码的解释性程序语言。

    xmlhttprequest

    ie浏览器把xmlhttp

    var http_request = new ActiveXObject("Msxml2.XMLHTTP");
    
    
    var http_request = new ActiveXObject("Microsoft.XMLHTTP");
    
    

    mozailla,safari等其他浏览器

    var http_request = new XMLHttpRequest();
    
    
    if(window.XMLHttpRequest){
    http_request = new XMLHttpRequest();
    }else if(window.ActiveXObject){
     try{
     http_request = new ActiveXObject("Msxml2.XMLHTTP");
     }catch(e){
     try{
     http_request = new ActiveXObject("Msxml2.XMLHTTP");
    }catch(e){
     try{
     http_request = new ActiveXObject("Microsoft.XMLHTTP");
    }catch(e){}
    }
    }
    
    

    XMLHttpRequest对象的常用方法:

    open()方法用于设置进行异步请求目标的url

    open("method", "url" [,asyncFlag [,"userName" [, "password"]]])
    
    

    send()方法用于向服务器发送请求

    send(content)
    
    

    setRequestHeader()方法

    setRequestHeader()方法为请求的http头设置值

    setRequestHeader("label","value")
    
    

    label用于指定http头,value用于指定http头设置值

    open()方法过后才能使用setRequestHeader()方法
    
    

    abort()方法
    abort()方法用于停止当前异步请求

    getAllResponseHeaders()方法
    getAllResponseHeaders()方法用于以字符串形式完整的http头信息。

    xmlhttpRequest对象常用的属性
    onreadystatechange 每个状态改变时都会触发这个事件处理器,通常会调用一个JavaScript函数。

    readyState 请求的状态:

    0 为未初始化
    1 为正在下载
    2 为已加载
    3 在交互中
    4 为完成
    
    

    responseText 服务器的响应,表示字符串

    responseXML 服务器的响应,表示xml

    status 返回服务器的http状态码
    statusText 返回http状态码对应的文本

    xml语言为可扩展的标记语言,提供了用于描述结构化数据的格式。xmlHttpRequest对象与服务器交换的数据,通常采用xml格式。

    dom为文档对象模型,为xml文档的解析定义了一组接口。

    在PHP中应用AJAX技术检测用户名

    <script language="javascript">
    var http_request = false;
    function createRequest(url) {
        //初始化对象并发出XMLHttpRequest请求
        http_request = false;
        if (window.XMLHttpRequest) {                                        //Mozilla等其他浏览器
            http_request = new XMLHttpRequest();
            if (http_request.overrideMimeType) {
                http_request.overrideMimeType("text/xml");
            }
        } else if (window.ActiveXObject) {                              //IE浏览器
            try {
                http_request = new ActiveXObject("Msxml2.XMLHTTP");
            } catch (e) {
                try {
                    http_request = new ActiveXObject("Microsoft.XMLHTTP");
               } catch (e) {}
            }
        }
        if (!http_request) {
            alert("不能创建XMLHTTP实例!");
            return false;
        }
        http_request.onreadystatechange = alertContents;                     //指定响应方法
    
        http_request.open("GET", url, true);                                 //发出HTTP请求
        http_request.send(null);
    }
    function alertContents() {                                               //处理服务器返回的信息
        if (http_request.readyState == 4) {
            if (http_request.status == 200) {
                alert(http_request.responseText);
            } else {
                alert('您请求的页面发现错误');
            }
        }
    }
    </script>
    <script language="javascript">
    function checkName() {
        var username = form1.username.value;
        if(username=="") {
            window.alert("请填写用户名!");
            form1.username.focus();
            return false;
        }
        else {
            createRequest('checkname.php?username='+username+'&nocache='+new Date().getTime());
        }
    }
    </script>
    
    
    <?php
        header('Content-type: text/html;charset=GB2312');       //指定发送数据的编码格式为GB2312
        $link=mysql_connect("localhost","root","root");
        mysql_select_db("db_database",$link);
        $GB2312string=iconv( 'UTF-8', 'gb2312//IGNORE' , $RequestAjaxString);           //Ajax中先用encodeURIComponent对要提交的中文进行编码
        mysql_query("set names gb2312");
        $username=$_GET[username];
        $sql=mysql_query("select * from tb_user where name='".$username."'");
        $info=mysql_fetch_array($sql);
        if ($info){
            echo "很报歉!用户名[".$username."]已经被注册!";
        }else{
            echo "祝贺您!用户名[".$username."]没有被注册!";
        }
    ?>
    
    

    类别添加

    <script language="javascript">
    var http_request = false;
    function createRequest(url) {
        //初始化对象并发出XMLHttpRequest请求
        http_request = false;
        if (window.XMLHttpRequest) {                                        //Mozilla等其他浏览器
            http_request = new XMLHttpRequest();
            if (http_request.overrideMimeType) {
                http_request.overrideMimeType("text/xml");
            }
        } else if (window.ActiveXObject) {                              //IE浏览器
            try {
                http_request = new ActiveXObject("Msxml2.XMLHTTP");
            } catch (e) {
                try {
                    http_request = new ActiveXObject("Microsoft.XMLHTTP");
               } catch (e) {}
            }
        }
        if (!http_request) {
            alert("不能创建XMLHTTP实例!");
            return false;
        }
        http_request.onreadystatechange = alertContents;                     //指定响应方法
    
        http_request.open("GET", url, true);                                 //发出HTTP请求
        http_request.send(null);
    }
    function alertContents() {                                               //处理服务器返回的信息
        if (http_request.readyState == 4) {
            if (http_request.status == 200) {
                sort_id.innerHTML=http_request.responseText;                //设置sort_id HTML文本替换的元素内容
            } else {
                alert('您请求的页面发现错误');
            }
        }
    }
    </script>
    <script language="javascript">
    function checksort() {
        var txt_sort = form1.txt_sort.value;
        if(txt_sort=="") {
            window.alert("请填写文章类别!");
            form1.txt_sort.focus();
            return false;
        }
        else {
            createRequest('checksort.php?txt_sort='+txt_sort);
        }
    }
    </script>
    
    
    <?php
        $link=mysql_connect("localhost","root","root");
        mysql_select_db("db_database",$link);
        $GB2312string=iconv( 'UTF-8', 'gb2312//IGNORE',$RequestAjaxString);         //Ajax中先用encodeURIComponent对要提交的中文进行编码
        mysql_query("set names gb2312");
        $sort=$_GET[txt_sort];
        mysql_query("insert into tb_sort(sort) values('$sort')");
        header('Content-type: text/html;charset=GB2312');       //指定发送数据的编码格式为GB2312
    ?>
    <table border="0" cellpadding="0" cellspacing="0">
      <tr>
        <td>
        <select name="select" >
        <?php
            $link=mysql_connect("localhost","root","root");
            mysql_select_db("db_database23",$link);
            $GB2312string=iconv( 'UTF-8', 'gb2312//IGNORE' , $RequestAjaxString);           //Ajax中先用encodeURIComponent对要提交的中文进行编码
            mysql_query("set names gb2312");
            $sql=mysql_query("select distinct * from tb_sort group by sort");
            $result=mysql_fetch_object($sql);
            do{
                header('Content-type: text/html;charset=GB2312');       //指定发送数据的编码格式为GB2312
        ?>
        <option value="<?php echo $result->sort;?>" selected><?php echo $result->sort;?></option>
        <?php
            }while($result=mysql_fetch_object($sql));
        ?>
        </select>
    
    

    xml基础技术

    了解xml,使用simpleXML解析文档的方法
    遍历xml文档,修改,保存xml,创建xml文档的方法

    xml语法
    xml文档结构,xml声明,处理指令,注解,xml元素,xml属性,使用cdata标记,xml命令空间。

    XML文档结构

    <?xml version="1.0" encoding="gb2312" standalone="yes"?>
    
    
    <?xml-stylesheet type="text/css" href="111.css"?>
    
    

    XML声明

    <?xml version="1.0" encoding="gb2312" standalone="yes"?>
    
    
    image

    处理指令

    <?xml-stylesheet type = "text/css" href="111.css"?>
    
    
    <?处理指令名 处理执行信息?>
    
    

    xml-stylesheet:样式表单处理指令
    type="text/css":设定了文档所使用的样式是css
    href="111.css":设定了样式文件的地址

    image

    XML属性

    <标签 属性名="属性值" 属性名=""…>内容</标签>
    
    
    image

    SimpleXML
    创建SimpleXML对象
    Simplexml_load_file()函数,将指定的文件解析到内存中
    Simplexml_load_string()函数,将创建的字符串解析到内存当中
    Simplexml_load_date()函数,将一个使用dom函数创建的domDocument对象导入到内存当中

    遍历所有子元素
    children()方法和foreach循环语句可以遍历所有子节点元素

    遍历所有属性
    SimpleXML对象中的attributes()方法

    <?xml version="1.0" encoding="GB2312"?>
    <exam>
    
    </exam>
    
    
    <?php
    header('Content-Type:text/html;charset=utf-8');
    ?>
    
    <?php
    /*  第一种方法  */
    $xml_1 = simplexml_load_file("5.xml");
    print_r($xml_1);
    /*  第二种方法  */
    $str = <<<XML
    <?xml version='1.0' encoding='gb2312'?>
    <Object>
        <ComputerBook>
            <title>PHP</title>
        </ComputerBook>
    </Object>
    XML;
    $xml_2 = simplexml_load_string($str);
    echo '<br>';
    print_r($xml_2);
    /*  第三种方法  */
    $dom = new domDocument();
    $dom -> loadXML($str);
    $xml_3 = simplexml_import_dom($dom);
    echo '<br>';
    print_r($xml_3);
    ?>
    
    
    <?php
    header('Content-Type:text/html;charset=utf-8');
    ?>
    <style type="text/css">
    
    <?php
    $str = <<<XML
    <?xml version='1.0' encoding='gb2312'?>
    <object>
        <book>
            <computerbook>PHP</computerbook>
        </book>
        <book>
            <computerbook>PHP</computerbook>
        </book>
    </object>
    XML;
    $xml = simplexml_load_string($str);
    foreach($xml->children() as $layer_one){
        print_r($layer_one);
        echo '<br>';
        foreach($layer_one->children() as $layer_two){
            print_r($layer_two);
            echo '<br>';
        }
    }
    ?>
    
    
    
    <?php
    $str = <<<XML
    <?xml version='1.0' encoding='gb2312'?>
    <object name='commodity'>
        <book type='computerbook'>
            <bookname name='22'/>
        </book>
        <book type='historybook'>
            <booknanme name='111'/>
        </book>
    </object>
    XML;
    $xml = simplexml_load_string($str);
    foreach($xml->children() as $layer_one){
        foreach($layer_one->attributes() as $name => $vl){
            echo $name.'::'.$vl;
        }
        echo '<br>';
        foreach($layer_one->children() as $layer_two){
            foreach($layer_two->attributes() as $nm => $vl){
                echo $nm."::".$vl;
            }
            echo '<br>';
        }
    }
    ?>
    
    
    <?php
        header('Content-Type:text/html;charset=utf-8');
    ?>
    
    <?php
    $str = <<<XML
    <?xml version='1.0' encoding='gb2312'?>
    <object name='商品'>
        <book>
            <computerbook>P123</computerbook>
        </book>
        <book>
            <computerbook name='456'/>
        </book>
    </object>
    XML;
    $xml = simplexml_load_string($str);
    echo $xml[name].'<br>';
    echo $xml->book[0]->computerbook.'<br>';
    echo $xml->book[1]->computerbook['name'].'<br>';
    ?>
    
    
    <?php
    header('Content-Type:text/html;charset=utf-8');
    $str=<<<XML
    <?xml version='1.0' encoding='gb2312'?>
    <object name='商品'>
        <book>
            <computerbook type='12356'>123</computerbook>
        </book>
    </object>
    XML;
    
    $xml = simplexml_load_string($str);
    echo $xml[name].'<br />';
    $xml->book->computerbook['type'] = iconv('gb2312','utf-8','PHP123');
    $xml->book->computerbook = iconv('gb2312','utf-8','PHP456');
    echo $xml->book->computerbook['type'].' => ';
    echo $xml->book->computerbook;
    ?>
    
    
    <?php
    $xml = simplexml_load_file('10.xml');
    $xml->book->computerbook['type'] = iconv('gb2312','utf-8','PHP1');
    $xml->book->computerbook = iconv('gb2312','utf-8','PHP2');
    $modi = $xml->asXML();
    file_put_contents('10.xml',$modi);
    $str = file_get_contents('10.xml');
    echo $str;
    ?>
    
    
    <?php
        //Message_XML类,继承PHP5的DomDocument类
        class Message_XML extends DomDocument{
        //属性
        private $Root;
        //方法
        //构造函数
        public function __construct() {
            parent:: __construct();
        //创建或读取存储留言信息的XML文档message.xml
        if (!file_exists("message.xml")){
            $xmlstr = "<?xml version='1.0' encoding='GB2312'?><message></message>";
            $this->loadXML($xmlstr);
            $this->save("message.xml");
        }
        else
            $this->load("message.xml");
    }
    public function add_message($user,$address){  //添加数据
        $Root = $this->documentElement;
        //获取留言消息
        $admin_id =date("Ynjhis");
        $Node_admin_id= $this->createElement("admin_id");
        $text= $this->createTextNode(iconv("GB2312","UTF-8",$admin_id));
        $Node_admin_id->appendChild($text);
    
        $Node_user = $this->createElement("user");
        $text  = $this->createTextNode(iconv("GB2312","UTF-8",$user));
        $Node_user->appendChild($text);
    
        $Node_address = $this->createElement("address");
        $text= $this->createTextNode(iconv("GB2312","UTF-8",$address));
        $Node_address->appendChild($text);
    
        $Node_Record = $this->createElement("record");
        $Node_Record->appendChild($Node_admin_id);
        $Node_Record->appendChild($Node_user);
        $Node_Record->appendChild($Node_address);
        //加入到根结点下
        $Root->appendChild($Node_Record);
        $this->save("message.xml");  
        echo "<script>alert('添加成功');location.href='".$_SERVER['PHP_SELF']."'</script>";
    }
    public function delete_message($admin_id){  //删除数据
        $Root = $this->documentElement;
        $xpath = new DOMXPath($this);
        $Node_Record= $xpath->query("//record[admin_id='$admin_id']");
        $Root->removeChild($Node_Record->item(0));
        $this->save("message.xml");
        echo "<script>alert('删除成功');location.href='".$_SERVER['PHP_SELF']."'</script>";
    }
    
    public function show_message(){  //读取数据
        $root=$this-documentElement;
        $xpath=new DOMXPath($this);
    
        $Node_Record=$this->getElementsByTagName("record");
        $Node_Record_length=$Node_Record->length;
        print"<table width='506' bgcolor='#FFFFCC'><tr>";
        print"<td width='106' height='22' align='center'>";
        print"<b>用户名</b>";
        print"</td><td width='400' align='center'>";
        print"<b>留言信息</b></td></tr>";
    
        for($i=0;$i<$Node_Record->length;$i++){
            $k=0;
            foreach($Node_Record->item($i)->childNodes as $articles){
               $field[$k]=iconv("UTF-8","GB2312",$articles->textContent);
                $k++;
        }
        print"<table width='506' bgcolor='#FFFFCC'><tr>";
        print"<td width='100' height='22' align='center'>";
        print"$field[1]";
        print"</td><td width='300' align='left'>";
        print"$field[2]";
        print"</td><td width='100' align='center'>";
        print"<a href='?Action=delete_message&admin_id=$field[0]'>删除</a></td>";
        print"</tr></table>"; 
        }}
        public function post_message(){
            print "<table width='506' bgcolor='#FFFFCC'><form method='post' action='?Action=add_message'>";
            print "<tr><td  width='106'height='22'>&nbsp;&nbsp;&nbsp;&nbsp;用户名:</td><td><input type=text name='user' size=50></td></tr>";
            print "<tr><td width='106' height='22'>&nbsp;&nbsp;&nbsp;&nbsp;留言信息:</td><td width='400'><textarea name='address' cols='48' rows='5' id='address'></textarea></td></tr>";
            print "<tr><td width='106' height='30'>&nbsp;&nbsp;<input type='submit' value='添加数据'></td><td align='right'><a href=?Action=show_message>查看数据</a>&nbsp;&nbsp;&nbsp;&nbsp;</td></tr></form></table>";
        }
    
    }
    ?>
    
    <html>                                                                                                                           
        <head>                                                                                                                  
        <title>定义一个PHP读取XML类</title>                                                                                        
            <style>
            td,body{font-size:12px}
            a:link {
        text-decoration: none;
    }
    a:visited {
        text-decoration: none;
    }
    a:hover {
        text-decoration: none;
    }
    a:active {
        text-decoration: none;
    }
    </style>                                                                                      
        <meta http-equiv="Content-Type" content="text/html; charset=gb2312"></head>                                                                                                                        
    <body>                                                                                                                         
    <table width=506 height=50 border=0 cellpadding=0 cellspacing=0 bgcolor="#33BE6B">                                
    
            <tr>                                                                                                                         
              <td width="506" height=50 valign="bottom" background="title.gif"><table width="506">
                <tr>
                  <td height="24" align="right" scope="col">&nbsp;&nbsp;<a href=?Action=post_message>添加数据</a>&nbsp;&nbsp;&nbsp;</td>
                </tr>
              </table></td>
            </tr>  
            <?php                                                                                       
            $HawkXML = new Message_XML;     
            $Action ="";      
            if(isset($_GET['Action']))     
                  $Action = $_GET['Action'];                                                                                       
            switch($Action){                                                                                            
                case "show_message":        //查看                                                                               
                    $HawkXML->show_message();                                                                         
                    break;                                                                                                     
                case "post_message":        //提交                                                                               
                    $HawkXML->post_message();                                                                       
                    break;                                                                                                      
                case "add_message":          //添加                                                                            
                    $HawkXML->add_message($_POST['user'],$_POST['address']);                                             
                    break;    
                case "delete_message":      //删除
                    $HawkXML->delete_message($_GET['admin_id']);
                    break;
            }                                                                                                
           ?>   
    </table>                                                                                                                   
    </body>                                                                                                                      
    </html>                                                                                                                        
    
    
    <?php
        //Message_XML类,继承PHP5的DomDocument类
        class Message_XML extends DomDocument{
        //属性
        private $Root;
        //方法
        //构造函数
        public function __construct() {
            parent:: __construct();
        //创建或读取存储留言信息的XML文档message.xml
        if (!file_exists("message.xml")){
            $xmlstr = "<?xml version='1.0' encoding='GB2312'?><message></message>";
            $this->loadXML($xmlstr);
            $this->save("message.xml");
        }
        else
            $this->load("message.xml");
    }
    public function add_message($user,$address){  //添加数据
        $Root = $this->documentElement;
        //获取留言消息
        $admin_id =date("Ynjhis");
        $Node_admin_id= $this->createElement("admin_id");
        $text= $this->createTextNode(iconv("GB2312","UTF-8",$admin_id));
        $Node_admin_id->appendChild($text);
    
        $Node_user = $this->createElement("user");
        $text  = $this->createTextNode(iconv("GB2312","UTF-8",$user));
        $Node_user->appendChild($text);
    
        $Node_address = $this->createElement("address");
        $text= $this->createTextNode(iconv("GB2312","UTF-8",$address));
        $Node_address->appendChild($text);
    
        $Node_Record = $this->createElement("record");
        $Node_Record->appendChild($Node_admin_id);
        $Node_Record->appendChild($Node_user);
        $Node_Record->appendChild($Node_address);
        //加入到根结点下
        $Root->appendChild($Node_Record);
        $this->save("message.xml");  
        echo "<script>alert('添加成功');location.href='".$_SERVER['PHP_SELF']."'</script>";
    }
    
    public function show_message(){  //读取数据
        $root=$this-documentElement;
        $xpath=new DOMXPath($this);
    
        $Node_Record=$this->getElementsByTagName("record");
        $Node_Record_length=$Node_Record->length;
        print"<table width='506' bgcolor='#FFFFCC'><tr>";
        print"<td width='106' height='22' align='center'>";
        print"<b>用户名</b>";
        print"</td><td width='400' align='center'>";
        print"<b>留言信息</b></td></tr>";
    
        for($i=0;$i<$Node_Record->length;$i++){
            $k=0;
            foreach($Node_Record->item($i)->childNodes as $articles){
               $field[$k]=iconv("UTF-8","GB2312",$articles->textContent);
                $k++;
        }
        print"<table width='506' bgcolor='#FFFFCC'><tr>";
        print"<td width='100' height='22' align='center'>";
        print"$field[1]";
        print"</td><td width='400' align='left'>";
        print"$field[2]";
        print"</td>";
        print"</tr></table>"; 
        }}
        public function post_message(){
            print "<table width='506' bgcolor='#FFFFCC'><form method='post' action='?Action=add_message'>";
            print "<tr><td  width='106'height='22'>&nbsp;&nbsp;&nbsp;&nbsp;用户名:</td><td><input type=text name='user' size=50></td></tr>";
            print "<tr><td width='106' height='22'>&nbsp;&nbsp;&nbsp;&nbsp;留言信息:</td><td width='400'><textarea name='address' cols='48' rows='5' id='address'></textarea></td></tr>";
            print "<tr><td width='106' height='30'>&nbsp;&nbsp;<input type='submit' value='添加数据'></td><td align='right'><a href=?Action=show_message>查看数据</a>&nbsp;&nbsp;&nbsp;&nbsp;</td></tr></form></table>";
        }
    
    }
    ?>
    <html>                                                                                                                           
        <head>
        <title>使用XML来存储少量的数据</title>                                                                                 
        <style>
        td,body{font-size:12px}
        a:link {
        text-decoration: none;
    }
    a:visited {
        text-decoration: none;
    }
    a:hover {
        text-decoration: none;
    }
    a:active {
        text-decoration: none;
    }
    </style>                                                                                      
        <meta http-equiv="Content-Type" content="text/html; charset=gb2312"></head>                                                                                                                        
    <body>                                                                                                                         
    <table width=506 height=50 border=0 cellpadding=0 cellspacing=0 bgcolor="#33BE6B">                                
    
            <tr>                                                                                                                         
              <td width="506" height=50 valign="bottom" background="title.gif"><table width="506">
                <tr>
                  <td height="24" align="right" scope="col">&nbsp;&nbsp;<a href=?Action=post_message>添加数据</a>&nbsp;&nbsp;&nbsp;</td>
                </tr>
              </table></td>
            </tr>  
            <?php                                                                                       
            $HawkXML = new Message_XML;     
            $Action ="";      
            if(isset($_GET['Action']))     
                  $Action = $_GET['Action'];                                                                                       
            switch($Action){                                                                                            
                case "show_message":        //查看                                                                               
                    $HawkXML->show_message();                                                                         
                    break;                                                                                                     
                case "post_message":        //提交                                                                               
                    $HawkXML->post_message();                                                                       
                    break;                                                                                                      
                case "add_message":          //添加                                                                            
                    $HawkXML->add_message($_POST['user'],$_POST['address']);                                             
                    break;    }                                                                                                
             ?>
    </table>                                                                                                                   
    </body>                                                                                                                      
    </html>                                                                                                                        
    
    

    结言

    好了,欢迎在留言区留言,与大家分享你的经验和心得。

    感谢你学习今天的内容,如果你觉得这篇文章对你有帮助的话,也欢迎把它分享给更多的朋友,感谢。

    感谢!承蒙关照!您真诚的赞赏是我前进的最大动力!

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