WEBVTT 0 00:01.750 --> 00:02.770 All right, so here we are. 1 00:03.000 --> 00:09.180 I just want to discuss what happens when we include a character that is not specified in the encoding... 2 00:09.180 --> 00:12.270 type that we tell the browser that we accept. 3 00:12.990 --> 00:13.770 That's quite interesting. 4 00:14.370 --> 00:19.470 Let's just start off by creating a very simple form. The " "action" we don't need... 5 00:20.040 --> 00:22.320 and we're going to be getting into the action attribute later. 6 00:23.160 --> 00:25.920 Now, let me just show you a GET request. 7 00:27.490 --> 00:31.570 I want us to have our attribute, "accept-charset". 8 00:32.610 --> 00:35.510 Let's just start of by saying it's utf-8. 9 00:37.100 --> 00:42.620 Very simple. Then what I want to do is I want us to use the character theta. 10 00:43.940 --> 00:46.280 Theta, I've just copied it from a Word document... 11 00:46.510 --> 00:47.110 that's all I've done. 12 00:48.330 --> 00:54.920 This is theta. And the reason I'm using theta is that this is not included in the ISO character. 13 00:55.620 --> 00:58.110 So I just want to show you what happens. Anyway... 14 00:58.440 --> 01:00.960 now I want us to have our input here. 15 01:01.530 --> 01:03.850 The next thing we need on our input is a name... 16 01:03.870 --> 01:06.720 otherwise it won't be submitted to the server. 17 01:06.720 --> 01:09.810 And let's just give it a name of "yourName". 18 01:11.920 --> 01:16.210 Very simple. And then lastly, if we save this and you look at our browser right now, we don't have 19 01:16.210 --> 01:16.890 a submit button. 20 01:17.440 --> 01:20.950 So all I want to do is create a submit button. We're going to see this later on in the course... 21 01:21.400 --> 01:26.710 but for now, just know we can define another type on this input element being "submit". 22 01:27.700 --> 01:32.680 And we can give it a value of "submit me", or just "submit", to keep it simple. 23 01:34.080 --> 01:35.390 So far, so good, right? 24 01:35.490 --> 01:41.190 And what happens if we do type theta into this text box? Let me just zoom in a little bit so you can... 25 01:41.190 --> 01:42.930 see, we're putting theta in here. 26 01:43.860 --> 01:50.310 If we click submit, you can see in the URL, you've literally got the name of our variable, which... 27 01:50.310 --> 01:53.890 we've called yourName, and we've assigned that to the value of theta. 28 01:54.510 --> 01:59.910 And what's really cool, is that this is allowed because we've specified utf-8 as our encoding type... 29 01:59.920 --> 02:05.100 and as we've seen, it's got over 1.1 million values that it can represent, or characters... 30 02:05.100 --> 02:07.950 I should say. And theta is definitely one of them. 31 02:08.700 --> 02:15.330 The other thing you should bear in mind, is that the "method" and our "accept-charset" attributes here, are... 32 02:15.330 --> 02:16.320 the default values. 33 02:16.560 --> 02:19.080 So actually we could delete everything... 34 02:19.080 --> 02:22.710 we could refresh the page, let me just delete the URL... 35 02:24.400 --> 02:28.630 put in theta again, click submit, and we get exactly the same result. 36 02:29.350 --> 02:34.660 So this only becomes important, of course, when you want to start messing around with the accept-charset 37 02:34.740 --> 02:37.250 attribute, which we're going to do now, by the way. 38 02:37.840 --> 02:41.770 So let's define our character encoding now, accept-charset... 39 02:42.580 --> 02:45.370 but now this time, I want us to use ISO. 40 02:48.340 --> 02:54.580 Nowwwww things are going to get interesting. Let's delete the URL, so it's very clean. Let's say the... 41 02:54.580 --> 02:58.410 use types theta, and let the user now click submit. 42 02:58.420 --> 02:59.370 What do you think is going to happen? 43 03:02.210 --> 03:07.390 We'll look at that, we get thrown back to us, a weird looking URL with a whole lot of percentage... 44 03:07.400 --> 03:07.880 signs. 45 03:09.000 --> 03:14.610 And it's very hard for the server, if not impossible sometimes, to actually determine what the character... 46 03:14.610 --> 03:16.710 encoding of such a request was. 47 03:17.310 --> 03:17.850 Why? 48 03:18.270 --> 03:24.780 Because the server usually assumes that it is the same as the encoding the page containing the form... 49 03:24.780 --> 03:25.560 was submitted in. 50 03:26.130 --> 03:31.590 In other words, the server is going to assume in our instance here, that the encoding type is utf-8, 51 03:31.980 --> 03:37.530 and it's going to try and decode that information using utf-8, and it's not going to work. 52 03:37.710 --> 03:42.540 So to cut a long story short, once you start adding characters outside of your defined character... 53 03:42.540 --> 03:43.260 encoding type... 54 03:43.680 --> 03:46.410 a lot of strange things start to happen. 55 03:46.710 --> 03:49.350 And it's also very browser dependent, I might add. 56 03:49.680 --> 03:51.450 Different browsers do different things. 57 03:51.720 --> 03:55.800 Browsers might replace the unsupported characters with useless question marks, 58 03:56.160 --> 04:00.990 they may attempt to fix the characters, for example, smart quotes to regular quotes... 59 04:01.560 --> 04:07.920 some browsers might replace the character with a character entity reference, or some browsers might 60 04:07.920 --> 04:13.980 send it anyway as a different character encoding that what you specified in the form, mixing it in with... 61 04:13.980 --> 04:19.680 the original encoding of your entire document. Whew, I know, I've just said a lot. 62 04:20.130 --> 04:23.640 And bear in mind the example we looked at, was on Chrome... 63 04:23.640 --> 04:30.300 and what Chrome has tried to do, is it's trying to replace the unknown character with a character entity 64 04:30.300 --> 04:31.620 reference in the browser. 65 04:31.950 --> 04:33.420 I know that might be a bit confusing. 66 04:33.420 --> 04:33.950 Don't worry. 67 04:34.230 --> 04:41.790 In the next lecture, let me just explain a bit more exactly why we see these weird numbers with percentage... 68 04:41.790 --> 04:42.700 signs everywhere. 69 04:43.020 --> 04:46.440 This is really, really interesting and it is very advanced. 70 04:46.440 --> 04:51.330 And I know we are very early on in the course, so I don't want to scare you. If you're not quite following 71 04:51.330 --> 04:51.480 me... 72 04:51.480 --> 04:52.080 it's okay. 73 04:53.050 --> 04:56.230 We're going to get through it together. I'll see you in the next lecture.