What is the difference between

[BrianM]

=

 

==

 

and

 

===

 

What is the difference between the single, double and triple equal signs, and is there anything higher than 3 used at once?

[amites]

take a look at the PHP manual

 

http://www.php.net/manual/en/language.operators.php

[GreenUser]

One = is the same as, to define

Two = is equal to, compare

Three = equal variables and same type

 

Haven't seen too much of three being used, interesting.

[BrianM]

something like

 

<?php
if ($GLOBALS['text_dir'] === 'rtl') {
    echo '*,';
}
echo $GLOBALS['cfg']['NaviWidth'];
if ($GLOBALS['text_dir'] === 'ltr') {
    echo ',*';
}
?>

[zenag]

see this example....it displays null if both values are empty...
example1:
<?
if($_POST["submit"]=='submit')
{
if($_POST["text"]=="")
{
echo "null value in text";
}
if($_POST["name"]==="")
{
echo "null value in name";
}
}
?>
<form action="" method="post">
<br />
<input type="text" name="text" />
<input type="text" name="name" />
<input type="submit" name="submit" value="submit" />
</form>

example2:

<?
if($_POST["submit"]=='submit')
{
if($_POST["text"]=="")
{
echo "null value in text";
}
if($_POST["name"]==="")
{
echo "null value in name";
}
}
?>
<form action="" method="post">
<br />

<input type="text" name="name" />
<input type="submit" name="submit" value="submit" />
</form> 
it displays same result ..." null values in text null values in text"

example3:

<?
if($_POST["submit"]=='submit')
{
if($_POST["text"]=="")
{
echo "null value in text";
}
if($_POST["name"]==="")
{
echo "null value in name";
}
}
?>
<form action="" method="post">
<br />
<input type="text" name="text" />

<input type="submit" name="submit" value="submit" />
</form>

it displays only null values in text....  since "===" operator checks for values as well as occurence of text box name in the form...