PHP Variables

All variables in PHP start with a $ sign symbol. The script shows the variable type can be changed while program executes. 

 <html><body>
 <?php
  $x = 10;  echo "$x<br />";
  $x = "Hello!";  echo $x;
 ?>
 </body></html>

PHP Is a Loosely Typed Language
In PHP a variable does not need to be declared before being set. PHP converts the variable to the correct data type automatically, depending on how they are set. To concatenate two or more variables together, use the dot (.) operator. There are two string operators: the string concatenation operation (‘.’) and the concatenating assignment operator (‘.=’). The script shows variables do not need to be strings. They could be integer or real numbers or others. 

 <html><body>
 <?php
  $txt = "Hello, World!";
  $num = 1000 + $x;
  echo $txt . " " . $num ;
 ?>
 </body></html>
 
$x =

Variable Naming Rules
Review: PHP Variables
    Which PHP variable name is NOT valid?

      $myVar
      $myVar1
      $my$Var
      $my_Var
Result:        




      Did you ever walk in a room and forget why you walked in?    
      I think that’s how dogs spend their lives.    
      — Sue Murphy