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Ahtsham Ajus
Ahtsham Ajus

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Today I learned about Variables in PHP

The main way to store information in the middle of a PHP program is by using a variable.

  • Here are the most important things to know about variables in PHP.
  • All variables in PHP are denoted with a leading dollar sign ($).
  • The value of a variable is the value of its most recent assignment.
  • Variables are assigned with the = operator, with the variable on the left-hand side and
  • the expression to be evaluated on the right.
  • Variables can, but do not need, to be declared before assignment.
  • Variables in PHP do not have intrinsic types - a variable does not know in advance
  • whether it will be used to store a number or a string of characters.
  • Variables used before they are assigned have default values.
  • PHP does a good job of automatically converting types from one to another when
    PHP variables are Perl-lik
    PHP has a total of eight data types which we use to construct our variables:

  • Integers: are whole numbers, without a decimal point, like 4195.

  • Doubles: are floating-point numbers, like 3.14159 or 49.1.

  • Booleans: have only two possible values either true or false.

  • NULL: is a special type that only has one value: NULL.

  • Strings: are sequences of characters, like 'PHP supports string operations.'

  • Arrays: are named and indexed collections of other values.

  • Objects: are instances of programmer-defined classes, which can package up both other kinds of values and functions that are specific to the class.

  • Resources: are special variables that hold references to resources external to PHP
    (such as database connections).
    The first five are simple types, and the next two (arrays and objects) are compound - the
    compound types can package up other arbitrary values of arbitrary type, whereas simple
    types cannot.

Here's My PHP code

$x = 4;
function assignx () {$x = 0;
print "\$x inside function is $x.
print "\$x outside of function is $x.
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This will produce the following result.

$x inside function is 0.
$x outside of a function is 4.
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