2022年1月23日星期日

Blogger和WordPress的倒序显示

  Blogger和WordPress都可以通过一定的设置,变成一个只供自己查看的私人博客,相当于私人日记本,具体方法是,在博客设置里将其设置为只有作者才能查看,然后将博客设置为在一页内全部显示(比如设置单页文章1千篇),在博客安装一个倒序显示脚本,即可完成日记本的功能,可供导出和打印。

  除了打印,还可以将内容复制到TXT文件里,在邮箱里发送到Kindle邮箱,然后在自己的Kindle上看,相当于看书的体验。

  这里面的一个技术问题是如何在Blogger和WordPress里实现按照日期倒序显示(Reverse Post Order)。这里分别给出Blogger和WordPress实现倒序的方法。

  在Blogger中,页脚点击“添加小工具”,添加“HTML/JavaScript”微件,之后在微件内容里插入如下代码:

<!-- Start Post Reversal Code -->
<script type='text/javascript'>
//<![CDATA[
  // -----------------------------------------------------------------------------------------
  // Name   : PRS - Post Reversal Script for Blogger - Version 1.0
  // Author : David Yockey
  // URL    :   techsquirrels.blogspot.com/2012/04/swapping-to-reverse-post-order-on.html
  // -----------------------------------------------------------------------------------------
  // Temp variable used to shorten classname references
  var cn;
  // This function is called as needed in the main program below.
  function ReversePosts(BlogPostContainer,PostClass) {
    // Arguments:
    //    BlogPostContainer -- The node containing the posts to be reversed.
    //    PostClass -- The className of each of the posts in the container to be reversed.
    //                 (may be a single name from among names in the class attribute of the posts)
    // Flag for checking whether any posts are found
    var found=false;
    var BlogPosts = BlogPostContainer.childNodes;  // May include text-nodes containing
                                                   // whitespace in addition to post-nodes
    // Set index variables to top and bottom of BlogPosts list
    var i=0;
    var j=BlogPosts.length-1;
    for( ; ; ) {     // Start Endless Loop
      // Find next Post from the top
      while( (i < j) && (!(cn=BlogPosts[i].className) || !(cn.match(PostClass))) )
        ++i;
      // Find next Post from the bottom
      while( (i < j) && (!(cn=BlogPosts[j].className) || !(found=cn.match(PostClass))) ) // (see Footnote 1)
        --j;
      if( found && i < j ) {
        // Swap Posts (see Footnote 2)
        var tempi = BlogPosts[i].cloneNode(true);           // Store a copy of Post i in tempi
        var tempj = BlogPosts[j].cloneNode(true);           // Store a copy of Post j in tempj
        BlogPostContainer.replaceChild(tempi,BlogPosts[j]); // Replace Post j with Post i in tempi
        BlogPostContainer.replaceChild(tempj,BlogPosts[i]); // Replace Post i with Post j in tempj
      } else {
        // Done
        break;        // Break out of Endless Loop
      }
      ++i; --j;
    }
  }
  // Footnote 1:
  //   If a post is found from one end, then a post must necessarily be found from the other.
  //   So, recording and later checking for a post from one end is sufficient to ensure that
  //   one was found from both.
  //
  // Footnote 2:
  //   At least in Firefox 11.0 on Fedora Linux, replacing a child directly with another child
  //   causes some text-nodes containing whitespace to be deleted. That node deletion messes up
  //   the positions of the posts in the BlogPosts list. This is avoided by cloning both posts
  //   rather than just one and replacing both posts from the cloned copies.
  // *** MAIN POST REVERSAL PROGRAM ***
  // Magic Words
  var BlogWidget             = 'Blog1';
  var BlogPostContainerClass = 'blog-posts';
  var BlogPostClass          = 'date-outer';
  var DatePostContainerClass = 'date-posts';
  var DatePostClass          = 'post-outer';
  var Blog1 = document.getElementById(BlogWidget);
  // Find the node containing the blog posts
  var BlogPostContainer;
  var x=0;
  do {
    BlogPostContainer = Blog1.childNodes[x++];
  } while ( !(cn=BlogPostContainer.className) || !(cn.match(BlogPostContainerClass)) );
  // Reverse different day posts
  ReversePosts(BlogPostContainer,BlogPostClass);
  // Reverse same day posts - Loop thru contents of BlogPostContainer to find each day's posts
  var BlogPosts = BlogPostContainer.childNodes;
  for ( i = 0; i < BlogPosts.length; ++i ) {
    // Check for an actual post-node rather than a text-node or such
    if ( (cn=BlogPosts[i].className) && cn.match(BlogPostClass) ) {
      var DatePostContainer;
      x=0;
      // Find the node containing the posts to be reversed for the current day being processed
      do {
        DatePostContainer = BlogPosts[i].childNodes[x++];
      } while ( !(cn=DatePostContainer.className) || !(cn.match(DatePostContainerClass)) );
      ReversePosts(DatePostContainer,DatePostClass);
    }
  }
//]]>
</script>
<!-- End Post Reversal Code -->

  之后保存,设置“主页上显示的博文数量上限”的数量,然后打开页面即可看到倒序的文章。

  对于Wordpress来说,操作起来比较简单,安装一个名为“Chronological Posts”的Plugin即可实现倒序文章。

  从安全性来说,Blogger更为安全一些,谷歌帐号设置两步验证,在谷歌Blogger中写内容,然后设置只有自己只读,安装一个倒序显示脚本,然后复制到TXT文件里,在邮箱里发送到Kindle邮箱,然后在自己的Kindle上看,看完了就删,只要谷歌帐号不泄露,秘密的信息就不会泄漏。