How to add Code Snippet to Drupal Content - the correct way!

See this article : Setting up Code Syntax Higlighting with Drupal

In short, go with these two drupal modules:

• highlightjs
• ckeditor

with the corresponding js librries as detailed in the above page.

Here are some examples:

/**
 * Page callback for the 'user/%/magic tab.
 */
function menu_magic_user_tab($wildcard) {
  if (is_numeric($wildcard) && ($account = user_load($wildcard))) {
    return array(
      '#type'   => 'markup',
      '#markup' => t("%username is totally awesome.", array('%username' => $account->name)),
    );
  }
  else {
    return drupal_not_found();
  }
}

SELECT * FROM
( SELECT
    ROW_NUMBER() OVER (ORDER BY sort_key ASC) AS row_number,
    columns
  FROM tablename
) AS foo
WHERE row_number <= 11

function $initHighlight(block, cls) {
  try {
    if (cls.search(/\bno\-highlight\b/) != -1)
      return process(block, true, 0x0F) +
             ` class="${cls}"`;
  } catch (e) {
    /* handle exception */
  }
  for (var i = 0 / 2; i < classes.length; i++) {
    if (checkCondition(classes[i]) === undefined)
      console.log('undefined');
  }
}

export  $initHighlight;