Making the Form Work

Quick reference

• 00:04 We've got a form but it doesn't do anything yet.
• 00:07 So in this video, let's work on that functionality.
• 00:09 So when we click Submit, we know from back when we learned about forms,
• 00:13 we can pass whatever's in this field here with the, we can use this
• 00:18 super global of post with answer because that's what we named this thing.
• 00:23 So let's come up here to, let's see, here is where our numbers are output.
• 00:30 Let's just create a PHP tag and let's just echo out that thing.
• 00:36 So if we save this, come back here and hit reload, you see there's nothing there.
• 00:40 If we submit, say 6, boom, it hits six.
• 00:44 That seems to work.
• 00:46 But whenever we do that, these numbers change, and we can't really have that.
• 00:51 So I'm gonna show you a neat trick that we can use to pass
• 00:54 variables between pages with forms.
• 00:58 What we're gonna do is create a couple of input fields.
• 01:02 And let's name the first one num1, and give it a type="hidden".
• 01:10 Now, if we copy this, well actually, and let's give it a value equal to.
• 01:15 And let's create a PHP tag right here in the form, we can do that.
• 01:20 And let's echo out our num1 variable from up here.
• 01:25 So if we save this, or actually first before we do that, let's copy and
• 01:29 paste another one, and let's do num2, and we'll do the same thing here.
• 01:34 And actually let's give a space here, okay.
• 01:36 Now if we save this, come up here and hit reload, 2 and 8 are our numbers.
• 01:40 If we view the page source, we can see this hidden fields have two and
• 01:45 eight as the values but they're hidden so we can't actually see them on the screen.
• 01:50 But, that allows us to now pass these values to a new super global
• 01:54 just like we did with our answer.
• 01:56 So, let's copy this and let's paste out those two super globals.
• 02:01 So, the first one is num1 and then let's concatenate.
• 02:07 And put + and then concatenate again and put our second number,
• 02:13 num2 and another concatenation = and then our final concatenation.
• 02:19 Now let's save this, come back here and hit reload.
• 02:23 So, let's start from the beginning here.
• 02:25 So three plus four equals seven.
• 02:27 We submit, three plus four equals seven.
• 02:30 But there's something weird going on here.
• 02:32 When we come here the first time, this stuff is output.
• 02:35 Well that's because the first time we come here we haven't submitted these things,
• 02:40 so there's nothing to post.
• 02:42 So we can change that with a simple if statement.
• 02:44 Let's go if, and I'll just grab one of these.
• 02:51 If there is no num1 being posted,
• 02:55 then do nothing, else do all this stuff.
• 03:01 I'll save that, come back here and hit reload.
• 03:04 Nothing has been posted so nothing gets listed here.
• 03:07 But if we type something, 9 + 3 = 12.
• 03:11 Boom, it works.
• 03:12 But then again, up here, we're starting to get two different numbers but that's fine.
• 03:17 So we now have our form that's functional.
• 03:20 In the next video, we're gonna look at creating some logic to determine whether
• 03:25 this is a correct answer or not, and
• 03:27 then outputting a different message based on whether it's correct or incorrect.
• 03:31 So that's all for this video.

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