How to reduce repetitive code

Question

I've been searching for how to do this for a while but to no avail. Part of my template is using a lot of the same code, i.e. retrieving a specific page.

If this was Javascript I'd set up a function and keep calling the function. How can I call the code below repeatedly?

<?php
    $page = get_page_by_title('Excerpts Showreel'); <-- This piece of code will change
// the code below will never change.
?>
<?php
    $my_id = $page;
    $post_id = get_post($my_id, ARRAY_A);
    $title = $post_id['post_title'];
    $content = $post_id['post_content'];
?>
<?php 
    echo $content
?>

Answer 1

You can define your own custom functions in PHP just like you would in JavaScript. Here's your code example rewritten using a function:

$page = get_page_by_title('Excerpts Showreel'); <-- This piece of code will change

// the code below will never change.
function get_my_content( $page ) {
    $my_id = $page;
    $post_id = get_post($my_id, ARRAY_A);
    $title = $post_id['post_title'];
    $content = $post_id['post_content'];

    return $content;
}

echo get_my_content($page);

So long as you have your get_my_content() function defined, you can use it anywhere you need to.

Answer 2

the function get template part will do this perfectly. Just put your code in a separate file.

<?php get_template_part( 'loop', 'index' ); ?>

With the above, you would create a file in your themes folder called loop-index.php

Read up on it here: http://codex.wordpress.org/Function_Reference/get_template_part

Answer 3

Following on from @EAMann's answer, I'm assuming you want 'Excerpts Showreel' to be variable, and to return content based on passing the variable?

function mytheme_get_page_content_by_title( $title = false ) {

    if ( false == $title ) return;

    $page = get_page_by_title( $title );
    $my_id = $page;
    $post_id = get_post($my_id, ARRAY_A);
    $title = $post_id['post_title'];
    $content = $post_id['post_content'];

    return $content;
}

Then in your template:

echo mytheme_get_page_content_by_title( 'Excerpts Showreel' );

Note that you might want to sanitize the $title variable being passed into the function.

EDIT

I'm not sure why you'd need to return the title (it's what you start with, and pass to your function), but here you go:

function mytheme_get_page_details_by_title( $title = false ) {

    if ( false == $title ) return;

    $page = get_page_by_title( $title );
    $my_id = $page;
    $post_id = get_post($my_id, ARRAY_A);
    $posttitle = $post_id['post_title'];
    $postcontent = $post_id['post_content'];

    $details = array(
        'title' => $posttitle,
        'content' => $postcontent
    );

    return $details;
}

Then you'd have to pass it to a variable to use it in your template:

$mypostdetails = mytheme_get_page_details_by_title( 'Excerpts Showreel' );

echo $mypostdetails['title']; // print the post title
echo $mypostdetails['content']; // print the post content