isset()
functionYou can use the PHP isset()
function to test whether a variable is set or not. The isset()
will return FALSE
if testing a variable that has been set to NULL
.
Let's check out an example to understand how this function basically works:
<?php
$var1 = '';
if(isset($var1)){
echo 'This line is printed, because the $var1 is set.';
}
echo "<br>";
$var2 = 'Hello World!';
if(isset($var2)){
echo 'This line is printed, because the $var2 is set.';
}
echo "<br>";
// Unset the variable
unset($var2);
if(isset($var2)){
echo 'This line is printed, because the $var2 is set.';
} else{
echo 'This line is printed, because the $var2 is not set.';
}
echo "<br>";
$var3 = NULL;
if(isset($var3)){
echo 'This line is printed, because the $var3 is set.';
} else{
echo 'This line is printed, because the $var3 is not set.';
}
?>
i hope you like this small article.
Hi, My name is Harsukh Makwana. i have been work with many programming language like php, python, javascript, node, react, anguler, etc.. since last 5 year. if you have any issue or want me hire then contact me on [email protected]
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