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phpoutput-buffering

Why is ob_get_contents not working


I have this code:

<?php
ob_start();
?>
hi
<?php echo ob_get_contents(); ob_end_clean();

But nothing is outputted.
If I remove the ob_end_clean(); the output is hi hi. If ob_flush() isn't called at the end of the app, the contents are automatically flushed, again.

I need to use ob_get_contents() because I am going to implement a simple caching mechanism that saves the the output to a file.

Please help.

Thanks!


Solution

  • Update: I am surprised but your example does actually work with output buffering. I did not think that HTML between php tags would work but it does.

    <?php
    ob_start();
    ?>
    Hello World
    <?php 
    echo "Goodbye";
    $test = ob_get_contents(); ob_end_clean(); echo "output:".$test;
    ?>
    

    This outputs output: Hello World Goodbye.

    The problem is you are echoing ob_get_contents into the buffer. As your question in the comments was about templating, I still think you are going about output buffering wrong. You should push PHP variables into an HTML template, not pull an HTML template into a PHP script. You should also look into a controller/view solution but below is a basic example.

    Templating: For templating, a basic example could be:

    <?php
    ob_start();
    ...PHP LOGIC HERE...
    ...PHP LOGIC HERE...
    ...PHP LOGIC HERE...
    $content = ob_get_contents();
    ob_end_clean();
    ?>
    <html>
    <body>
    <div><?php echo $content; ?></div>
    </body></html>