Variable Function

Ø       gettype

• Return the type of php variable.
• Possible return value are Boolean, integer, double, string, array, null, object resources, user function.

            Syntax

                        String gettype(mixed $var)

Example

<?php

          $str ="Hello World";

          echo gettype($str);

          ?>

Output  

                   String

Ø       settype

• Set the type of variable.

            Syntax

                        bool settype(mixed $var, string type)

Parameter	Description
var	The variable being converted.
Type	Possible values of type are Boolean, integer, float, string, array, object, null.

Example

<?php

          $str ="Hello World";

          settype($str,"string")."<br/>";

          echo gettype($str);

          ?>

Output  

                   string

Ø       isset

• Determine whether a variable is set.
• Returns true if variable exits, false otherwise.

Syntax

                        bool isset(mixed $var[,mixed $var…] )

Example

<?php

          $str ="Hello World";

          if(isset($str))

          {

                   echo "variable is set.";

          }

          else

          {

                   echo "variable is not set.";

          }

          ?>

Output  

                   variable is set.

Ø       unset

• unset a given variable.
• unset() destroy the specified variables.

Syntax

                        void unset(mixed $var[,mixed $var…] )

Example

<?php

          $str ="Hello World";

          echo $str."<br/>";

          unset($str);

          echo "variable unset";

          ?>

Output  

                   Hello World

                   variable unset.

Ø       strval

• This function is used to convert any data type value of PHP into string value and will return string value.

Syntax

                        string strval(mixed $var)

Example

<?php

          $str ="Hello World";

          echo strval($str);

          ?>

Output  

                   Hello World

Ø       floatval

• This function is used to convert the mixed data type into the float data type.

Syntax

                        float floatval(mixed $var)

Example

<?php

          $str ="0.5";

          $num = floatval($str);

          echo gettype($num);

          ?>

Output  

                   Double

Ø       intval

• This function is used to convert the mixed data type into the integer data type.

Syntax

                        Integer intval(mixed $var)

Example

<?php

          $str ="5";

          $num = intval($str);

          echo gettype($num);

          ?>

Output  

                   Integer

Ø       print_r

• This function will display the array in the array in the format as it is declare in the code. The return type is void.

Syntax

                        void print_r(array variable)

Example

<?php

          $str ="5";

          $num = intval($str);

          echo gettype($num);

          ?>

Output  

                  Array ( [0] => 1 [1] => 2 )

Posted By : Hemangi Zala