Difference between revisions of "PHP-and-MySQL/C2/If-Statement/English-timed"
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− | |Welcome to this basic php Spoken Tutorial. Here we will discuss the ' | + | |Welcome to this basic '''php- Spoken Tutorial'''. Here we will discuss the '''if''' statement. |
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|00:06 | |00:06 | ||
− | |If you have written code before, you would have come across the ' | + | |If you have written '''code''' before, you would have come across the 'if' statement. |
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|00:11 | |00:11 | ||
− | | | + | |It's not much different in '''php'''. I'll '''execute''' one shortly and show you. |
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|00:16 | |00:16 | ||
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|00:18 | |00:18 | ||
− | |Okay, here is a brief about the ' | + | |Okay, here is a brief about the 'if' statement. It takes a condition. |
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|00:23 | |00:23 | ||
− | |If the condition is True, it executes one path of code. | + | |If the condition is '''True''', it executes one path of code. |
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|00:28 | |00:28 | ||
− | |If it is False, it will execute another path of code. | + | |If it is '''False''', it will execute another path of code. |
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|00:32 | |00:32 | ||
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|00:36 | |00:36 | ||
− | | | + | |'if' - inside the bracket is the condition to know whether 1 equals 1. |
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|00:41 | |00:41 | ||
− | |Notice I am using a double 'equal to' sign here. This is the comparison operator. | + | |Notice, I am using a double 'equal to' sign here. This is the comparison '''operator'''. |
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|00:47 | |00:47 | ||
− | |In another tutorial we're going to learn about operators. | + | |In another tutorial, we're going to learn about '''operators'''. |
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|00:50 | |00:50 | ||
− | |It reads as 'is equal to' though it is not the same as 'equals' | + | |It reads as 'is equal to' though it is not the same as 'equals'. |
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|00:56 | |00:56 | ||
− | |When we're using variables, | + | |When we're using variables, we want to compare we use 'double equal to'. |
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|01:02 | |01:02 | ||
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|01:12 | |01:12 | ||
− | |If | + | |If it's 'Not True', we'll say '''else'''. |
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|01:15 | |01:15 | ||
− | |The same structure - so two curly brackets. | + | |The same structure - so, two curly brackets. |
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|01:17 | |01:17 | ||
− | |For example, if 1 equals 1 we say echo 'True'. | + | |For example, '''if 1 equals 1''' we say '''echo''' 'True'. |
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|01:23 | |01:23 | ||
− | |If 1 is not equal 1, what we should get when we run our file is False. | + | |If 1 is not equal 1, what we should get when we run our file is '''False'''. |
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|01:30 | |01:30 | ||
− | |Since 1 is equal to 1 what we get when we run our file is True | + | |Since 1 is equal to 1, what we get when we run our file is '''True'''. |
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|01:36 | |01:36 | ||
− | |Let us change this | + | |Let us change this. If 1 equals 2, which it doesn't, then we'll get '''False'''. |
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|01:42 | |01:42 | ||
− | |So we would have already created a simple program to tell us if one number equals another. | + | |So, we would have already created a simple program to tell us if one number equals another. |
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|01:49 | |01:49 | ||
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|01:52 | |01:52 | ||
− | |So I will just add something more. I'll create a little program for a password access. | + | |So, I will just add something more. I'll create a little program for a password access. |
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|01:58 | |01:58 | ||
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|02:03 | |02:03 | ||
− | |Say the password is abc. | + | |Say, the '''$password''' is "abc". |
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|02:05 | |02:05 | ||
− | |I am going to incorporate a variable into my IF function by saying | + | |I am going to incorporate a variable into my '''IF''' function by saying: |
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|02:11 | |02:11 | ||
− | | | + | |if '''password''', remember double equals "def" |
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|02:15 | |02:15 | ||
− | | | + | |and I'll say '''Access granted'''. |
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|02:21 | |02:21 | ||
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|02:32 | |02:32 | ||
− | |So if it doesn't equal 'def', | + | |So, if it doesn't equal 'def', I'll say '''Access denied'''. |
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|02:39 | |02:39 | ||
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|02:42 | |02:42 | ||
− | |We're going to compare the password to 'def' | + | |We're going to compare the password to 'def' which is the stored password. |
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|02:50 | |02:50 | ||
− | |If this equals 'def', we're going to say 'Access granted' else 'Access denied'. | + | |If this equals 'def', we're going to say '''Access granted''' else '''Access denied'''. |
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|02:57 | |02:57 | ||
− | | | + | |Let's try this. |
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|03:00 | |03:00 | ||
− | |'Access denied'. This is because the passwords do not match. | + | |'''Access denied'''. This is because the passwords do not match. |
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|03:05 | |03:05 | ||
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|03:10 | |03:10 | ||
− | |Change this to 'def' and we'll get 'Access granted'. | + | |Change this to 'def' and we'll get '''Access granted'''. |
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|03:18 | |03:18 | ||
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|03:25 | |03:25 | ||
− | |To me that looks a lot neater. | + | |To me, that looks a lot neater. |
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|03:29 | |03:29 | ||
− | |Please note - there is no point in adding curly brackets if you have only one line of code for simple IF statements like these. | + | |Please note - there is no point in adding curly brackets if you have only one line of code for simple '''IF''' statements like these. |
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|03:37 | |03:37 | ||
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|03:42 | |03:42 | ||
− | |For example, | + | |For example, let's set a new variable here. |
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|03:46 | |03:46 | ||
− | | | + | |'''$access''' equals "Allowed". |
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|03:52 | |03:52 | ||
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|04:02 | |04:02 | ||
− | |It says an unexpected T_else on line 8 | + | |It says: an unexpected T_else on line 8. |
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|04:08 | |04:08 | ||
− | | | + | |Let's find line 8. It's here. The line before it is causing a problem. |
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|04:13 | |04:13 | ||
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|04:22 | |04:22 | ||
− | |We refresh this and Access is granted. | + | |We '''refresh''' this and '''Access is granted'''. |
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|04:25 | |04:25 | ||
− | |Now I've set a new variable, access to be allowed. | + | |Now I've set a new variable, '''access''' to be '''allowed'''. |
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|04:29 | |04:29 | ||
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|04:50 | |04:50 | ||
− | |This is Madhu dubbing for the Spoken Tutorial Project. Thanks for watching. Bye. | + | |This is Madhu, dubbing for the Spoken Tutorial Project. Thanks for watching. Bye. |
Latest revision as of 11:57, 5 December 2018
Time | Narration |
00:00 | Welcome to this basic php- Spoken Tutorial. Here we will discuss the if statement. |
00:06 | If you have written code before, you would have come across the 'if' statement. |
00:11 | It's not much different in php. I'll execute one shortly and show you. |
00:16 | So, let us start. |
00:18 | Okay, here is a brief about the 'if' statement. It takes a condition. |
00:23 | If the condition is True, it executes one path of code. |
00:28 | If it is False, it will execute another path of code. |
00:32 | For example - this is the structure. |
00:36 | 'if' - inside the bracket is the condition to know whether 1 equals 1. |
00:41 | Notice, I am using a double 'equal to' sign here. This is the comparison operator. |
00:47 | In another tutorial, we're going to learn about operators. |
00:50 | It reads as 'is equal to' though it is not the same as 'equals'. |
00:56 | When we're using variables, we want to compare we use 'double equal to'. |
01:02 | If you are going for the 'True' path, you can use two curly brackets. |
01:06 | We're going to open one here. |
01:08 | Our code will go in between the brackets. |
01:12 | If it's 'Not True', we'll say else. |
01:15 | The same structure - so, two curly brackets. |
01:17 | For example, if 1 equals 1 we say echo 'True'. |
01:23 | If 1 is not equal 1, what we should get when we run our file is False. |
01:30 | Since 1 is equal to 1, what we get when we run our file is True. |
01:36 | Let us change this. If 1 equals 2, which it doesn't, then we'll get False. |
01:42 | So, we would have already created a simple program to tell us if one number equals another. |
01:49 | This is quite a silly application for a program. |
01:52 | So, I will just add something more. I'll create a little program for a password access. |
01:58 | We are going to store the password in a variable here. |
02:03 | Say, the $password is "abc". |
02:05 | I am going to incorporate a variable into my IF function by saying: |
02:11 | if password, remember double equals "def" |
02:15 | and I'll say Access granted. |
02:21 | Sorry, I made a mistake. 'def' is the password we want to ask the user for. 'abc' is the password I'm inputting to the system. |
02:32 | So, if it doesn't equal 'def', I'll say Access denied. |
02:39 | The password that I've inputted is 'abc'. |
02:42 | We're going to compare the password to 'def' which is the stored password. |
02:50 | If this equals 'def', we're going to say Access granted else Access denied. |
02:57 | Let's try this. |
03:00 | Access denied. This is because the passwords do not match. |
03:05 | On this basis, you can see here that I've incorporated a variable. |
03:10 | Change this to 'def' and we'll get Access granted. |
03:18 | Because I have one line of code here and another one line of code here. |
03:22 | I can get rid of these curly brackets. |
03:25 | To me, that looks a lot neater. |
03:29 | Please note - there is no point in adding curly brackets if you have only one line of code for simple IF statements like these. |
03:37 | If you're going to have a line after line here, you'll need the curly brackets. |
03:42 | For example, let's set a new variable here. |
03:46 | $access equals "Allowed". |
03:52 | That's just basically another line of code. |
03:57 | But when I try and run this, we get an error. |
04:02 | It says: an unexpected T_else on line 8. |
04:08 | Let's find line 8. It's here. The line before it is causing a problem. |
04:13 | Which is why we need to add our curly brackets back in to cater for two or more lines of code. |
04:22 | We refresh this and Access is granted. |
04:25 | Now I've set a new variable, access to be allowed. |
04:29 | This won't be of much help. |
04:32 | But I was just giving you an example. |
04:35 | You can see this is still a single line and these are double lines and you can't mix them up. |
04:40 | OK, so I've created a variable. I've incorporated it into an 'IF' statement. Hope this was useful. |
04:46 | This brings us to end of this tutorial. |
04:50 | This is Madhu, dubbing for the Spoken Tutorial Project. Thanks for watching. Bye. |