PHP data type conversion_PHP tutorial

PHP does not require (or support) explicit type definitions in variable definitions; the variable type is determined based on the context in which the variable is used. In other words, if a string value is assigned to the variablevar,varbecomes a string. If you assign an integer value tovar, it becomes an integer.

An example of PHP's automatic type conversion is the plus sign "+". If any operand is a floating point number, all operands are treated as floating point numbers, and the result is also a floating point number. Otherwise the operands are interpreted as integers and the result is also an integer. Note that this does not change the types of the operands themselves; only how the operands are evaluated and the type of the expression itself is changed.

Type casting

The allowed casts are:

• (int), (integer) - converted tointeger
• (bool), (boolean) - Convert toboolean
• (float), (double), (real) - Convert toFloat (float)
• (string) - Convert tostring (string)
• (binary) - convert to binarystring (string)(PHP 6)
• (array) - Convert toarray (array)
• (object) - Convert toobject (object)
• (unset) - convert to NULL (PHP 5)

(binary) conversion will prefix the result with 'b', new in PHP 5.2.1.

Note that spaces and tabs are allowed within brackets

Convertstring(string)literals and variables to binarystring(string):

 = (binary) = b"binary string"?>

If you want to change the type of a variable, see settype();

settype—Set the type of variable

Set the type of variablevartotype.

typeare:

• "boolean" (or "bool" since PHP 4.2.0)
• "integer" (or "int" since PHP 4.2.0)
• "float" (only available after PHP 4.2.0, "double" used in older versions is now deprecated)
• "string"
• “array”
• "object"
• "null" (since PHP 4.2.0)

ReturnsTRUEon success, orFALSEon failure.

intval(), floatval(), strval(), these three functions can also be converted