PHP-and-MySQL/C4/Cookies-Part-1/English

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Time Narration
0:00 Welcome to this tutorial on php cookies.
0:04 Cookies are a very important part when creating special websites where you store information about a user.
0:11 The definition of a cookie is a set of data stored on your computer or the user's computer by the web server.
0:18 This means, that when we go to a website, our details are stored and are used when we visit it again, provided we select an option like 'Remember me'.
0:30 So you don't have to keep logging in.
0:32 But if you didn't check a button like 'remember me', you will probably be dealing with sessions which close as soon as the user closes the browser.
0:42 So sessions are killed straight away however cookies are stored for later use.
0:50 So lets begin right away and see how to create a cookie.
0:53 You do this by using the setcookie function.
0:55 The function takes 5 parameters but I will use just 3.
1:00 The first vital one I will use is the name of the cookie which I will set to 'name'.
1:05 The second one is the data that needs to be stored inside this cookie and I'll type Alex here.
1:12 Now the next one's a bit more tricky.
1:15 Its the time in which it expires.
1:18 Now this needs to be set in seconds.
1:21 And to represent this I am going to create a variable called 'exp' for expire and this will be equal to the time.
1:28 Let me add some value here.
1:31 At the moment I am adding zero.
1:33 So if I echo this out and get rid of this cookie function for now.
1:39 I'm just echoing out the time here just to show you what it does.
1:43 So lets refresh. So you can see quite a lot of digits here.
1:47 Now this is the unique time-stamp.
1:50 And the unique time-stamp is the number of seconds before January the 1st 1970.
1:56 So January the 1st at 12 am ummmm...... in the year 1970.
2:02 So you can see it here - I think the number of seconds in here equates to a date in the future.
2:10 So for example, at this moment you can see this 88, now 89 and as I keep refreshing, by every second this increases.
2:20 So yes, this is quite useful way of adding a specific value here.
2:28 Now we need to find out the time in seconds of a day because I want this cookie to expire in a day.
2:34 So I multiply 24 by 60 to get the number of minutes in a day.
2:39 And then multiply the answer by 60 to get the number of seconds in a day which is 86,400.
2:47 So if I replace zero with 86400, we have the variable "expire" that now holds the time in the future by a day.
2:56 To save time, I am copying this and I will add my expire variable here.
3:02 So this function will set our cookie called 'name' with a value of 'Alex' and it will expire in a day - read in seconds using the time function here.
3:13 So lets refresh this page and hey! we can see we have no errors which means it has worked.
3:19 Now what I'll do is I'll use block commenting to comment out all of these.
3:23 And below this I'll echo out this cookie.
3:26 But the reason I have commented this is because you don't need to set a cookie every time the user comes into the page.
3:33 If you are using a log in script and you let the user log into your website, you would need to issue this only once and then the cookie will be stored.
3:41 And you could use it within this time that we have set here.
3:46 So what I'll do is I'll set echo and I'll use a dollar sign, sorry, underscore cookie.
3:52 Inside here is the name of the cookie so I'll type 'name'. Refresh and you can see 'Alex'.
3:59 You can check it out. Even if I close my browser, restart my computer and came back into this page, it will still read Alex because its been stored into the computer.
4:11 Okay now if had to set another cookie, let's say, I set another cookie here and this will be 'age' and my age is 19.
4:24 And my expiry time I'll just keep as this.
4:29 So lets just put this up here.
4:31 We can replace the block commenting with line-comment to keep it neat.
4:36 So for our expiry time I'll set another cookie in here.
4:41 And that’ll have the same expiry time. Lets see if I can get it right.
4:46 Okay so we'll get rid of this.
4:48 We’ve set another cookie with the same expiry time.
4:51 Lets refresh. Okay that has been set.
4:55 So what I'll do is comment this out and here I will echo it out.
5:01 So you see we can set more than one cookie in a page. Lets refresh that and we can get 19.
5:07 Now we can also set a cookie in a single sentence.
5:11 For that I'll type echo underscore cookie, name and the concatenate "is" and then concatenate my age.
5:27 Therefore we will have a sentence saying Alex is 19 just from the cookies that we've stored.
5:34 And again if I close my browser or restart my computer or come back two hours later, this information will still be there stored on this computer ready to be used by this page.
5:44 So you can see that they are really very useful to use and really easy to create as well and easy to echo out the user.
5:53 Now there's a function we can use called 'print r' or 'print underscore r'.
5:58 And we can echo out 'dollar underscore cookie' here. We can align it a bit later...
6:05 Refresh this and you can see we've got an array here and we have a different value.
6:12 We have got name and that is equal to Alex and we've got an age which is equal to 19.
6:22 So these are cookies and they have been set and these are the values of the cookies.
6:27 This can be very useful if you want to echo this out to yourself.
6:31 Okay now there is another function which I will cover in the second part of this tutorial and I'll use an 'if' statement to find out if a cookie is set or not.
6:41 And I'll also show you how to unset a cookie.
6:45 So join me in part 2 and thanks for watching. This is Evan Varkey dubbing for the Spoken Tutorial Project. Bye.

Contributors and Content Editors

Chandrika, Pravin1389