Adding Pagination Links

Back in the catalog.php file, 0:00 Directly before the unordered list, we're gonna add our pagination links. 0:06 We'll start with a new div. 0:10 We'll give this a class of pagination. 0:11 Then we'll add Pages, with a colon. 0:18 Next we need to add some code to show our pages and links. 0:23 We can use a while loop to create a count of numbers 0:26 that are less than the total number of pages. 0:29 Let's start by opening our php block. 0:32 First, we need an incremental variable. 0:41 Will name this i, we'll set it to zero initially. 0:44 Then we can do a while ($i < $total_pages) {. 0:49 Then we need to add one to i every time we loop. 1:03 We could use, I equals I plus one. 1:08 Or we could simplify this. 1:13 I plus equals one. 1:16 Or we can simplify this it even further. 1:19 I plus plus. 1:24 All of these options do the same thing. 1:26 The last one is the most common way of adding a single number to an integer, so 1:29 we use that. 1:33 Speaking of common practice, usually you'll see these three lines 1:35 combine into a single statement using for instead of while. 1:38 We'll move i = 0 into our for, 1:42 including the semi colon. 1:47 We then add i plus plus to the end separated by a semi colon. 1:53 We don't need a semi colon at the end. 2:01 The only difference in writing a statement this way 2:04 is that adding one to the i variable won't happen until the end of the loop. 2:06 So when working with the i variable within the loop, 2:11 our first loop through I will be equal to zero. 2:14 We want to start with page one. 2:18 So we'll change our initial value to one. 2:21 We also need to change our comparison. 2:26 We'll change it to less-then or equal-to total pages. 2:29 If i is less than or equal to our total pages, we want to enter our loop. 2:34 Now, what do we want to do in the loop? 2:41 Well, that depends on what page we're on. 2:42 So let's start with the conditional. 2:45 If i is equal to our current page, 2:48 then we just want to echo out i. 2:56 We'll surround this by a span tag. 3:00 We can leave our single variable right in our double quotes. 3:06 If it's not equal to our current page, then we want to link to that page. 3:13 So we're going to echo a link. 3:18 We're going to link to our catalog page but 3:25 we need to know if we're on a category page or not. 3:28 So add a conditional. 3:31 If it's set, then we want to make sure our link links to that category page. 3:41 And we finish with an ampersand. 3:54 Finally we'll add our page number. 3:57 Well use I for that and we'll close out our link. 4:02 We'll use I for the display again and are a tag. 4:06 A couple things to clean up, let's finish our if else statement. 4:09 And let's add a space at the beginning of our numbers, just so they're separated. 4:16 Now we're ready to check this out in our browser. 4:22 Great, now we see all the pages and we can navigate between those pages. 4:26 I want to add these links both above the results and below the results. 4:35 So let's go back to our page. 4:39 I don't want to repeat this code so let's add it to a variable name pagination. 4:42 We're gonna put this up in our initial php block. 4:53 Because there are quotes within this quote, 5:06 we need to escape them using our slash quote. 5:09 We'll use .= for concatenation. 5:18 We don't need our php tag here since we're already in our php block. 5:24 Let's also remove the closing tag here. 5:30 Instead of echo we're going to use pagination .=. 5:35 Add our final closing div and our pagination variable is ready to go. 5:52 We can clean this up a little here, and now let's display it where we want. 6:01 We want to echo pagination. 6:16 Above our on ordered list. 6:21 And also below, let's save this page and refresh our browser. 6:27 Great, our pagination links are above our results and below our results. 6:36 Fantastic job. 6:42 We've cleaned up our calls to the database so 6:44 that we're only pulling the information we need. 6:46 We've limited the number of results per page so 6:49 we don't overwhelm visitors to our catalog. 6:52 And we've set up linking between pages, both for our full catalog and for 6:54 our category pages. 6:59 You are ready for our final feature. 7:01 Search capabilities. 7:03