The difference and using method of PHP isset and unset

Many beginners will isset and unset to confuse, in fact, they are the difference between the two is very big, can say that there is no relationship oh, I think may be like it, so think so oh, then let's take a look at the grammar of Isset.

Isset (variable);

Description

Isset is used to determine whether a variable exists, if it returns true otherwise it returns false, and this variable is useful to us and we can use it to determine if a variable such as Get post is in OH.

Isset instance "

$a = "Test";
$b = "Anothertest";

echo isset ($a)? ' True ': ' false ';

The output is: true

Now let's take a look at the unset example.

$a = "Test";
$b = "Anothertest";

unset ($a);

echo isset ($a)? ' True ': ' false ';

The output is false;

You know why? Because Unset is the destruction of variables Oh.

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