PHP-and-MySQL/C2/If-Statement/English-timed

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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 Its 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, when 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 its '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 Lets 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, lets 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 Lets find line 8. Its 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.

Contributors and Content Editors

Minal, Pratik kamble, Sandhya.np14