The difference between equal and equal in php

The equal and equal operators in PHP are == and === respectively. They are comparison operators. Comparison operators allow you to compare two values. So what are the specific differences between the two operators equal (==) and full equal (also called absolute equal (===)) in PHP?

Below we will introduce to you the difference between == and === with a simple code example.

1. When we use the == symbol for comparison

The code example is as follows:

<?php
$a=true ;
$b=8;
$c=&#39;8&#39;;

if($a==&#39;true&#39;){
    echo "相等";
}else{
    echo "不相等";
}
echo &#39;<br>&#39;;
if($b==$c){
    echo "相等";
}else{
    echo "不相等";
}

At this time, the judgment output is as follows:

2. When we use the === symbol to compare

The code example is as follows:

<?php
$a=true ;
$b=8;
$c=&#39;8&#39;;

if($a==="true"){
    echo "相等";
}else{
    echo "不相等";
}
echo &#39;<br>&#39;;
if($b===$c){
    echo "相等";
}else{
    echo "不相等";
}

The judgment output at this time is as follows:

In the example, the variable $a is a Boolean type , and $b is an integer type , $c is a string, and "true" represents the string .

Difference:

== operator means that if $b is equal to $c, it returns true. (Equal values) The

=== operator means that if $b is equal to $c, and they have the same type, then return true. (Equal values ​​and equal types)

As in the above example:

true=="true", if their values ​​are equal, true will be returned;

true===" true", if their values ​​are equal but their types are different, false is returned.

Similarly:

8==‘8’ returns true;

8===‘8’ returns false.

Note: In PHP, the basic assignment operator is "=". It means that the left operand is set to the value of the right-hand expression.

This article is about the specific differences between equal == and all equal === in PHP. I hope it will be helpful to friends in need!

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