| ##################### |
| Template Parser Class |
| ##################### |
| |
| The Template Parser Class enables you to parse pseudo-variables |
| contained within your view files. It can parse simple variables or |
| variable tag pairs. If you've never used a template engine, |
| pseudo-variables look like this:: |
| |
| <html> |
| <head> |
| <title>{blog_title}</title> |
| </head> |
| <body> |
| |
| <h3>{blog_heading}</h3> |
| |
| {blog_entries} |
| <h5>{title}</h5> |
| <p>{body}</p> |
| {/blog_entries} |
| </body> |
| </html> |
| |
| These variables are not actual PHP variables, but rather plain text |
| representations that allow you to eliminate PHP from your templates |
| (view files). |
| |
| .. note:: CodeIgniter does **not** require you to use this class since |
| using pure PHP in your view pages lets them run a little faster. |
| However, some developers prefer to use a template engine if they work |
| with designers who they feel would find some confusion working with PHP. |
| |
| .. important:: The Template Parser Class is **not** a full-blown |
| template parsing solution. We've kept it very lean on purpose in order |
| to maintain maximum performance. |
| |
| Initializing the Class |
| ====================== |
| |
| Like most other classes in CodeIgniter, the Parser class is initialized |
| in your controller using the $this->load->library function:: |
| |
| $this->load->library('parser'); |
| |
| Once loaded, the Parser library object will be available using: |
| $this->parser |
| |
| The following functions are available in this library: |
| |
| $this->parser->parse() |
| ====================== |
| |
| This method accepts a template name and data array as input, and it |
| generates a parsed version. Example:: |
| |
| $this->load->library('parser'); |
| |
| $data = array( |
| 'blog_title' => 'My Blog Title', |
| 'blog_heading' => 'My Blog Heading' |
| ); |
| |
| $this->parser->parse('blog_template', $data); |
| |
| The first parameter contains the name of the :doc:`view |
| file <../general/views>` (in this example the file would be called |
| blog_template.php), and the second parameter contains an associative |
| array of data to be replaced in the template. In the above example, the |
| template would contain two variables: {blog_title} and {blog_heading} |
| |
| There is no need to "echo" or do something with the data returned by |
| $this->parser->parse(). It is automatically passed to the output class |
| to be sent to the browser. However, if you do want the data returned |
| instead of sent to the output class you can pass TRUE (boolean) to the |
| third parameter:: |
| |
| $string = $this->parser->parse('blog_template', $data, TRUE); |
| |
| $this->parser->parse_string() |
| ============================== |
| |
| This method works exactly like parse(), only accepts a string as the |
| first parameter in place of a view file. |
| |
| Variable Pairs |
| ============== |
| |
| The above example code allows simple variables to be replaced. What if |
| you would like an entire block of variables to be repeated, with each |
| iteration containing new values? Consider the template example we showed |
| at the top of the page:: |
| |
| <html> |
| <head> |
| <title>{blog_title}</title> |
| </head> |
| <body> |
| |
| <h3>{blog_heading}</h3> |
| |
| {blog_entries} |
| <h5>{title}</h5> |
| <p>{body}</p> |
| {/blog_entries} |
| </body> |
| </html> |
| |
| In the above code you'll notice a pair of variables: {blog_entries} |
| data... {/blog_entries}. In a case like this, the entire chunk of data |
| between these pairs would be repeated multiple times, corresponding to |
| the number of rows in a result. |
| |
| Parsing variable pairs is done using the identical code shown above to |
| parse single variables, except, you will add a multi-dimensional array |
| corresponding to your variable pair data. Consider this example:: |
| |
| $this->load->library('parser'); |
| |
| $data = array( |
| 'blog_title' => 'My Blog Title', |
| 'blog_heading' => 'My Blog Heading', |
| 'blog_entries' => array( |
| array('title' => 'Title 1', 'body' => 'Body 1'), |
| array('title' => 'Title 2', 'body' => 'Body 2'), |
| array('title' => 'Title 3', 'body' => 'Body 3'), |
| array('title' => 'Title 4', 'body' => 'Body 4'), |
| array('title' => 'Title 5', 'body' => 'Body 5') |
| ) |
| ); |
| |
| $this->parser->parse('blog_template', $data); |
| |
| If your "pair" data is coming from a database result, which is already a |
| multi-dimensional array, you can simply use the database result_array() |
| function:: |
| |
| $query = $this->db->query("SELECT * FROM blog"); |
| |
| $this->load->library('parser'); |
| |
| $data = array( |
| 'blog_title' => 'My Blog Title', |
| 'blog_heading' => 'My Blog Heading', |
| 'blog_entries' => $query->result_array() |
| ); |
| |
| $this->parser->parse('blog_template', $data); |
| |