Question

我正在制作一个查看计数系统。但问题是，无论何时人重新加载页面，视图都会增加为了阻止它，我使用了一个会话变量代码如下：

    if ($_SESSION['var'] == NULL){
    $start = "UPDATE table SET views = views+1 WHERE value = $value";
        $_SESSION['var'] = true;
}

如果刷新页面，会话变量保持不变，条件失败，没有任何反应。

问题：
但是，如果页面被关闭并重新打开，则视图不会增加而应该增加我究竟做错了什么？

我写了session_start()和PDO查询来执行该功能。

Answer 1

为了实现您的目标，您需要在浏览器选项卡/窗口关闭时销毁会话。因此，您需要一个在窗口关闭时销毁会话参数的Ajax请求。

引用本文：http://eureka.ykyuen.info/2011/02/22/jquery-javascript-capture-the-browser-or-tab-closed-event/

在您的网络根目录中，创建js / check_browser_close.js。

/**
 * This javascript file checks for the brower/browser tab action.
 * It is based on the file menstioned by Daniel Melo.
 * Reference: http://stackoverflow.com/questions/1921941/close-kill-the-session-when-the-browser-or-tab-is-closed
 */
var validNavigation = false;

function wireUpEvents() {
  /**
   * For a list of events that triggers onbeforeunload on IE
   * check http://msdn.microsoft.com/en-us/library/ms536907(VS.85).aspx
   *
   * onbeforeunload for IE and chrome
   * check http://stackoverflow.com/questions/1802930/setting-onbeforeunload-on-body-element-in-chrome-and-ie-using-jquery
   */
  var dont_confirm_leave = 0; //set dont_confirm_leave to 1 when you want the user to be able to leave withou confirmation
  var leave_message = 'You sure you want to leave?'
  function goodbye(e) {
    if (!validNavigation) {
      if (dont_confirm_leave!==1) {
        if(!e) e = window.event;
        //e.cancelBubble is supported by IE - this will kill the bubbling process.
        e.cancelBubble = true;
        e.returnValue = leave_message;
        //e.stopPropagation works in Firefox.
        if (e.stopPropagation) {
          e.stopPropagation();
          e.preventDefault();
        }
        //return works for Chrome and Safari
        return leave_message;
      }
    }
  }
  window.onbeforeunload=goodbye;

  // Attach the event keypress to exclude the F5 refresh
  $(document).bind('keypress', function(e) {
    if (e.keyCode == 116){
      validNavigation = true;
    }
  });

  // Attach the event click for all links in the page
  $("a").bind("click", function() {
    validNavigation = true;
  });

  // Attach the event submit for all forms in the page
  $("form").bind("submit", function() {
    validNavigation = true;
  });

  // Attach the event click for all inputs in the page
  $("input[type=submit]").bind("click", function() {
    validNavigation = true;
  });

}

// Wire up the events as soon as the DOM tree is ready
$(document).ready(function() {
  wireUpEvents();
});

还要在您的Web根目录中创建以下.html来测试上述Javascript文件。

<html>
  <head>
    <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.4/jquery.min.js"></script>
    <script type="text/javascript" src="js/check_browser_close.js"></script>
  </head>
  <body>
    <h1>Eureka!</h1>
      <a href="http://www.google.com">Google</a>
      <a href="http://www.yahoo.com">Yahoo</a>
      <a href="http://ykyuen.wordpress.com">Eureka!</a>
  </body>
</html>

现在您需要修改代码以调用服务器端文件以使用Ajax销毁会话。

检查是否设置了变量，然后相应地执行该功能

1 个答案: