PHP-and-MySQL/C2/Arrays/English
From Script | Spoken-Tutorial
Revision as of 19:01, 1 December 2012 by Pravin1389 (Talk | contribs)
Time | Narration |
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0:00 | Hello and welcome to the tutorial on Arrays. |
0:03 | Arrays allow the user to store more than one piece of data inside a variable |
0:08 | For example the variable days would be called as an array |
0:12 | Inside a pair of parenthesis we're going to have more than one value |
0:18 | So, I'll pick 5 values for this and have every day of the week inside each of these. |
0:22 | I'll have Monday, Tuesday, Wednesday, Thursday and Friday - just 5 days of the week, that saves us |
0:39 | Say for example day one is Monday, day two is Tuesday and so on. |
0:49 | Hope you get the picture |
0:51 | This is a much easier and more efficient way of calling a variable with more more than one piece of data inside it |
00:59 | Please note these can also be numbers, or whatever data that you decide you require inside them. |
1:06 | Now, to echo out our array, I'm going to say echo days |
1:11 | Now, you find that this doesn't work. |
1:15 | This is what happens when we open up our page |
1:19 | We just get 'Array' echoed out. |
1:22 | Now, 'Array' is not anywhere inside here. |
1:24 | So, what PHP has done is echoed out the fact that what we have is an array. |
1:30 | Now, to call a specific element inside an array, you might want to call it element, in some places they call it id tags or elements of an array. |
1:41 | We're going to use square brackets and we'll call the position of the element inside the array. |
1:45 | So, you may think this is one, two, three, four, five. |
1:49 | However because of the numbering system, the standard numbering system, we are starting with zero, one, two, three and four. |
1:57 | So, for example if I wanted to echo out Monday that would be zero, so, you put zero in that and you have Monday echoed out. |
2:06 | The same with one would be Tuesday and four, which is the last element in the array, would be Friday. |
2:18 | Okay, so, we're going to go ahead and I'm going to show you how to assign values in a different way into an array |
2:26 | Now, let me start from the beginning of what I want to say. |
2:29 | I'm going to create an array, but I'm going to create it specifically. |
2:37 | So, days zero equals Monday, days one equals Tuesday |
2:52 | Now, you may think - what's the point of this? I mean, what I'm doing here essentially is creating what I said earlier would be bit of a hassle. |
3:04 | I mean I could say day 1 equals, you know and day 2 equals, and you could do it like that. |
3:14 | However, what we're still doing here is putting into an array. |
3:19 | So, it may still contain the same structure but we're assigning it in a different way. |
3:24 | So you can do it like that. Let me get rid of this. I always prefer to do it like this. |
3:32 | I find this much cleaner, much simpler and just to let you know - you can bring this down like this. |
3:43 | However if you prefer to view it, I mean if I, sorry, I'll redo that. |
3:49 | If I save this now, refresh, nothing's changed. |
3:53 | There are no errors, we still get the same structure, we've just moved it down on lines |
4:00 | There's the line terminator at the end of your function and not at the the end of every line, so, don't get confused with that. |
4:09 | Okay, so, let's now go back to this. |
4:14 | Okay, so, that's the basic array and how to create values for it in two different ways and how to call values for it. |
4:22 | So, for example if I was saying echo Today is days and then I can say zero. |
4:33 | Now, you can see already that I've highlighted this in context - I've highlighted that in green |
4:41 | Now, if you refresh this, you'll see this is Monday. |
4:44 | Now don't get confused, I do recommend you to use contexts. |
4:48 | However, this isn't the standard way that contact recognizes the coding. |
4:53 | What it would look better is - you'll see that when we write it down here we could say echo 'days' and zero, you can see how that's in red to show an integer, a number. |
5:08 | The way it would like you to write is, like that and we can see that's fine |
5:15 | But you can incorporate an array into your string in order to echo it out. |
5:22 | Anyway, I'm going to go on to associative arrays where we're going to assign id tags in a way where we hold a value for each...how can I describe that value for each sort of identity. |
5:36 | If you don't follow then this is the way I'm going to create it. |
5:40 | I'm going to say ages equals array, now inside, I'm going to say 'Alex' |
6:03 | Now, instead of going on and saying Billy and then Kyle which are the three names I'm going to use, I'm going to say nineteen, fourteen and eighteen |
6:16 | Basically using equals and greater than sign. |
6:24 | Now, what this is done is instead of our array elements as in this being called by zero, this being called by one, this being called by two. |
6:34 | This is now called as 'Alex', this is called as 'Billy' and this is called as 'Kyle' but their values are fourteen, nineteen and eighteen. |
6:44 | So, really, it would be the same as writing that. Lets get rid of that and calling this as zero, one and two. |
6:54 | And to make it a bit more friendly, and a bit easier to remember, a bit easier to call, we can now say, echo out 'ages', 'Alex', like that. |
7:05 | So, this will echo out nineteen, as we refresh and see there - nineteen. The same if you do it with 'Billy' and the same with 'Kyle'. |
7:22 | So, when you're half way through a program and instead of saying aah I'll have to go back to the top and count along each row and say "Is this zero, one, two or three I can't remember?" |
7:38 | This is much easier to do. Another useful way of doing this is, if I was to say array one is equal to 'Alex' and then two is equal to 'Billy'. |
7:50 | We are not starting at zero and then one. We're starting at one and two, so that you find that is easier to remember. |
8:00 | So, we can now say echo, 'ages' one, that comes out as 'Alex'. |
8:07 | We're not using zero for that, it's a lot more user friendly for you to program than to say, zero, one, two. |
8:16 | Try it out - work around it - see what's easiest for you. |
8:21 | But I mean this to me is quite pointless because I'm in the mood of using zero, one, two. |
8:27 | But if you want to use it like I have before or like this or assign a string value to any data types then that's the way to do it |
8:36 | Okay, that's the basics of arrays, I have another tutorial on multidimensional arrays. |
8:44 | Its a separate tutorial. Please watch it. |
8:47 | That's all in this tutorial. Thanks for watching. This is Arvind dubbing for the Spoken Tutorial project. Bye. |