Write and read the contents of a PHP file

Aug 28, 2020 PHP XML JSON

Write file

file_put_contents(“file location”,“contents to write”); file_put_contents has a return value so it can be checked with an if statement

<?php
    $check = file_put_contents("news_data/php_lesson.text","2020-08-28, writing file");
    if ($check){
        print ("write complete");
    }else{
        print ("write error");
    }
    ?>

Read file

The return value of file_fet_contents becomes the read data

<?php
    $check = file_get_contents("news_data/news.text");
    print ($check);
    ?>

With read_file, you can print the return value without printing In this case, the read data cannot be processed

<?php
    readfile("news_data/news.text");
    ?>

Add data

.= will be added after the string

<?php
    $news = file_get_contents("news_data/news.text");
    $news .= "Additional data";
    file_put_contents("news_data/news.text",$news);
    print ($news)
    ?>

If you want to add before the string

<?php
    $news = file_get_contents("news_data/news.text");
    $news = "Additional data". $news;
    file_put_contents("news_data/news.text",$news);
    print ($news)
    ?>

Read XML information

What is XML

XML is a type of markup language for describing the appearance and structure of text. Available in various fields that can be expanded. Generally used for RSS (update information).

<?php
    $xmlTree = simplexml_load_file('http://nakata.net/feed/');

    foreach ($xmlTree->channel->item as $item):
        ?>

        ・<a href="<?php print($item->link); ?>"><?php print($item->title); ?></a>

    <?php
    endforeach;
    ?>

The relationship of properties is like this,

access the elements inside item is an array so store it as $item

<channel>
<item>
<title></title>
<link></link>
</item>
</channel>

##JSON

JSON is an abbreviation for JavaScript Object Notation, which is a text-based data format similar to XML. Since it is short and easy to understand, it is used not only in JavaScript.

json content is after get_contents It can be converted into a PHP object by decoding Structure is different in xml and json

 <?php
    $file = file_get_contents('https://h2o-space.com/feed/json/');
    $json =json_decode($file);

    foreach ($json-> items as $item):
        ?>
        ・<a href="<?php print($item->url); ?>"><?php print($item->title); ?></a>

    <?php
    endforeach;
    ?>