PHP博客类别重复

Question

I have got a question regarding setting up proper categories for my posts that would be done automatically. I'm using PHP.

Here is my sample example document from the database:

   {
        "_id" : "css-clearfix-explained",
        "title" : "CSS Clearfix Explained",
        "category" : [ 
            "CSS/HTML", 
            " Wordpress"
        ],
        "date_time" : ISODate("2014-08-13T21:03:45.367Z"),
        "description" : "Blalalal ",
        "content" : " ",
        "author" : "Maciej Sitko"
    }

So, for that purpse I wrote the code that inserts the categories in the view page, to be more specific, it inserts them into the table. This is the code:

<?php if(!isset($_GET['cat'])) {
                $categories = $collection->find();?>

            <table class="table table-hover table-striped">
                <thead class='table-head' >
                    <tr ><th colspan='2'>Categories</th></tr>
                </thead>

                <tbody>

                    <?php foreach($categories as $category) { 
                        foreach($category as $keys) { 
                            if((is_array($keys)) && (!empty($keys))) {
                                foreach($keys as $key => $value)  { ?>

                                   <tr>
                                       <td><a class="normalize" href="">
                                           <?php echo $keys[$key]; ?></a></td>
                                       <td class="small"> Posts</td>
                                   </tr>

                    <?php } } } } ?>

                </tbody>
            </table>

The problem is, and you see it (I bet it), that when it is executed this way there would be duplicates of the categories in the table shown. How can I prevent those categories from repeating themselves in the listing? I know its a rookie question, but I'm still learning.

Answer 1

You could write $category into an array and every iteration - before displaying your data - you could check if $category is already in there. You could use "in_array": http://php.net/manual/de/function.in-array.php

<?php if(!isset($_GET['cat'])) {
        $categories = $collection->find();?>

        <table class="table table-hover table-striped">
            <thead class='table-head' >
                <tr ><th colspan='2'>Categories</th></tr>
            </thead>

            <tbody>

                <?php 
                    $uniqueCats = array();
                    foreach($categories as $category) { 
                    foreach($category as $keys) { 
                        if((is_array($keys)) && (!empty($keys))) {
                            foreach($keys as $key => $value)  { 
                            if( in_array($value, $uniqueCats) ) { continue; }
                            $uniqueCats[] = $value;
                             ?>

                               <tr>
                                   <td><a class="normalize" href="">
                                       <?php echo $value; ?></a></td>
                                   <td class="small"> Posts</td>
                               </tr>

                <?php } } } } ?>

            </tbody>
        </table>

I hope that's what you were looking for :) The code/variables slightly differs from how I would read the data in the example so I might have misinterpreted your question :)