Php 如何应用recaptcha？

最近，垃圾邮件越来越多

所以，我想知道如何应用recaptcha

代码附在下面

我自己问你问题

请回复。多谢各位

<div class="letterbox">
                    <form method="post" name="enewsform" id="enewsform" action="enewsletter_ins.php">
                    <h3 class="tit2">Subscribe To Newsletter</h3>
                    <div style="margin-top:10px;">
                        <label class="tit2">Name 
                          <input type="text" name="name" value="" /></label>
                        <label class="tit2">Email Address 
                          <input type="text" name="email" value="" /></label>
                        <input type="button" value="subscribe" class="btn_letter"  onclick="sendData(document.enewsform)" />
                        <div class="g-recaptcha" data-sitekey="site_key"></div>
                    </div>
                    </form>
                    <script type="text/javascript">
                    <!--
                        function sendData(f){
                            if(f.name.value==""){
                                alert("Required to name.");
                                f.name.focus();
                                return false;
                            }
                            if(f.email.value==""){
                                alert("Required to email.");
                                f.email.focus();
                                return false;
                            }
                            if (f.email.value.search(/(\S+)@(\S+)\.(\S+)/) == -1 ) {
                               alert("Not Valid Email."); 
                                f.email.focus();
                               return false;
                            }
                            f.submit();
                        }
                    //-->

<div class="letterbox">
                    <form method="post" name="enewsform" id="enewsform" action="enewsletter_ins.php">
                    <h3 class="tit2">Subscribe To Newsletter</h3>
                    <div style="margin-top:10px;">
                        <label class="tit2">Name 
                          <input type="text" name="name" value="" /></label>
                        <label class="tit2">Email Address 
                          <input type="text" name="email" value="" /></label>
                        <input type="button" value="subscribe" class="btn_letter"  onclick="sendData(document.enewsform)" />
                       <?php
          require_once('recaptchalib.php');
          $publickey = "your_public_key"; // you got this from the signup page
          echo recaptcha_get_html($publickey);
        ?>
                    </div>
                    </form>

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下载recaptcha PHP文件：

然后简单地把它放在你的HTML中

最近，垃圾邮件越来越多

所以，我想知道如何应用recaptcha

代码附在下面

我自己问你问题

请回复。多谢各位

<div class="letterbox">
                    <form method="post" name="enewsform" id="enewsform" action="enewsletter_ins.php">
                    <h3 class="tit2">Subscribe To Newsletter</h3>
                    <div style="margin-top:10px;">
                        <label class="tit2">Name 
                          <input type="text" name="name" value="" /></label>
                        <label class="tit2">Email Address 
                          <input type="text" name="email" value="" /></label>
                        <input type="button" value="subscribe" class="btn_letter"  onclick="sendData(document.enewsform)" />
                        <div class="g-recaptcha" data-sitekey="site_key"></div>
                    </div>
                    </form>
                    <script type="text/javascript">
                    <!--
                        function sendData(f){
                            if(f.name.value==""){
                                alert("Required to name.");
                                f.name.focus();
                                return false;
                            }
                            if(f.email.value==""){
                                alert("Required to email.");
                                f.email.focus();
                                return false;
                            }
                            if (f.email.value.search(/(\S+)@(\S+)\.(\S+)/) == -1 ) {
                               alert("Not Valid Email."); 
                                f.email.focus();
                               return false;
                            }
                            f.submit();
                        }
                    //-->

<div class="letterbox">
                    <form method="post" name="enewsform" id="enewsform" action="enewsletter_ins.php">
                    <h3 class="tit2">Subscribe To Newsletter</h3>
                    <div style="margin-top:10px;">
                        <label class="tit2">Name 
                          <input type="text" name="name" value="" /></label>
                        <label class="tit2">Email Address 
                          <input type="text" name="email" value="" /></label>
                        <input type="button" value="subscribe" class="btn_letter"  onclick="sendData(document.enewsform)" />
                       <?php
          require_once('recaptchalib.php');
          $publickey = "your_public_key"; // you got this from the signup page
          echo recaptcha_get_html($publickey);
        ?>
                    </div>
                    </form>

订阅时事通讯
名称
电子邮件地址

要验证它，请在服务器端执行以下操作：

<?php
  require_once('recaptchalib.php');
  $privatekey = "your_private_key";
  $resp = recaptcha_check_answer ($privatekey,
                                $_SERVER["REMOTE_ADDR"],
                                $_POST["recaptcha_challenge_field"],
                                $_POST["recaptcha_response_field"]);

  if (!$resp->is_valid) {
    // What happens when the CAPTCHA was entered incorrectly

  } else {
    // Your code here to handle a successful verification

  }
  ?>

---

未解决此问题。通常在我们的新信中注册，而无需通过recaptcha。