Comparison operators in Php

This tutorial is about Comparison Operators.Now “Comparison Operator” is basically to compare one or more values. We can compare any amount of values in a single statement.In this tutorial we will compare three values via demonstration.Now for this example, we are going to use “if statement” , I had shown you example about If Statement in my previous tutorials .

code for if Statement Condition true (Screenshot1):-

Screenshot1

<?php
$number1 = 10;
$number2 = 9;
if (true) {
echo 'inside.';
}
?>

Output (Screenshot2) :-

Screenshot2

In this code, condition evaluates either true or false. If I write true it will execute it and inside the browser it will display it and if I will write false it will not execute inner side of “if statement” example.

code for if Statement Condition false (Screenshot3):-

Screenshot3

<?php
 
$number1 = 10;
$number2 = 9;

if (false) {

echo 'inside.';

}

?>

output (Screenshot4) :-

Screenshot4

In this code it automatically evaluates “False” by false keyword. Now its same as we do 1==1. It just contain “double equal to” sign to compare variables. Now always remember when we assign values we use single equal sign (=) and in comparison we use double equal to sign (==) for comparing two variables.

Code for comparison operators Example (Screenshot5):-

Screenshot5

<?php
$number1 = 10;
$number2 = 9;
if (1==1) {
echo 'inside.';
}
?>

Output (Screenshot6):-

Screenshot6

In this example we are comparing variables such as number one is equal to number one, condition is true so,it will echo out the result as you seen in screenshot6.

Code for comparison operators Example (Screenshot7):-

Screenshot7

<?php
$number1 = 10;
$number2 = 9;
 
if (1==2) {
echo 'inside.';
}
?>

Output (Screenshot8):-

Screenshot8

In this example number one is not equal to number two then it will evaluate false condition and will not echo out anything as result as u seen in (screenshot 8).

Other Comparison Operators Examples

Code for comparison operators Example (Screenshot9):-

Screenshot9

<?php
$number1 = 10;
$number2 = 9;
if (1!=2) {
echo 'inside.';
}
?>

output (Screenshot10):-

Screenshot10

In this example we are using exclamation mark (!) which means not number one is not(!) equal to number two, then it evaluates true which will echo out as result.

Code for comparison operators Example (Screenshot11):-

Comparison Operators Screenshot11

<?php
$number1 = 10;
$number2 = 9;
if (1!=1) {
echo 'inside.';
}
?>

output (Screenshot12):-

Screenshot12

In this example we are using exclamation mark (!) which means not number one is not(!) equal to number one, then it evaluates false which will echo out as result.

Code for comparison operators Example (Screenshot13):-

Screenshot13

<?php
$number1 = 10;
$number2 = 9;
 
if($number1>$number2) {
echo 'Yes.';
}else {
echo 'No.';
}
?>

Output Screenshot14

Screenshot14

In this example we are using greater than(>) and smaller than(<)comparison operators. Now in this example, condition is if number1 is greater then number 2 then echo out yes or else no, but condition is true so it will echo out yes.

Now Try Some Examples with yourself giving you code copy and paste see results :-

Code for Example 1 (Screenshot15):-

Screenshot15

<?php



$number1 = 10;

$number2 = 9;



if($number1<$number2) {

echo 'Yes.';

}else {

echo 'No.';

}

?>

Code for Example 2 (Screenshot16):-

Screenshot16

<?php



$number1 = 10;

$number2 = 9;



if($number1>=$number2) {

echo 'Yes.';

}else {

echo 'No.';

}

?>

Code for Example 3 (Screenshot17):-

Screenshot17

Code for Example 4 (Screenshot18):-

Screenshot18

Code for Example 5 (Screenshot19):-

Screenshot19

Now comparison operators are very important when you work dynamically on website. For example, you want to submit form to check whether password is correct or not

Code for comparison operators (Screenshot20) :-

Screenshot20

Output (Screenshot21):-

Screenshot21

In this example we are matching password is correct or incorrect so, you can see its pretty easy and very useful to check conditions are whether True or False.In this, it will evaluate true as it matches variable values.

Code for comparison operators (Screenshot22) :-

Screenshot22

output (Screenshot23):-

Screenshot23

It will mismatch condition and evaluate false and will echo out incorrect .

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Variables in php

Variables

This tutorial is for variables. If you have worked with any other programming language you know what are variables for and what they will do.Values are assigned to variables and variables are of different types.Now in this tutorials i am going to show you how to declare variables by assigning values to standard structure and then variables are echoed out on the browser.So, Usually in programming languages such as JavaScript or for any other language like it we have to use keywords,for example in java we use “var” like var example.

<?php

var name = 'value';

?>

In php we don’t need any keywords to define anything only we need to assign it with “$” dollar sign notation and afterwards we can assign “_” sign or characters or strings or numeric characters also. Assigning can be done in upper-case and lower-case both.
Code for Variables(Screenshot1) :-

Code For Variables Screenshot1

<?php

echo $text = 'Hello World.';

echo $number = 100;

?>

output (Screenshot2) :-

Screenshot2

In Screenshot1 you can see codes for string.I have used sign ” notation for numeric value and i am not using any notation but only semi colon “;” . Semi colon “;” is a separator. Echo statementecho’s out the variables.We can assign any value to variables such as floating values, Boolean values,etc., but this we will see later on in if statements.

Code for variables different way (Screenshot3) :-

Code for Different types for variables Screenshot3

<?php

$text = 'Hello World.';

$number = 100;

 echo $text;

?>

Output (Screenshot4) :-

Variables Screenshot4

It will only echo variable $text contain because we only echoing $text variable Code for variables different way second example (Screenshot5):-

Screenshot5

<?php

$text = 'Hello world.";

$number = 100;

echo $number;

?>

Output(Screenshot6) :-

Screenshot6

It will echo out the content of variable $number because we are echoing variable $number. Programming languages are used todeclare different data’s, for example you want to take users age or take users name or anything you need to declare,so either you will store it as string data or you will store it as numerical data like integers (similarly for floats),which is somewhat tedious ! But, I would like to tell you an important aspect of php , that you don’t need to think about what data you are storing, you just simply need to assign “$” Sign in the prefix of variable name following with equal to and the variable value. Declaration of variables in php is quite easy.

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