A value can be converted to a string using the (string) cast or the strval() function.
String conversion is automatically done in the scope of an expression where a string is needed.
A boolean TRUE value is converted to the string "1".
Boolean FALSE is converted to "" (the empty string).
An integer or float is converted to a string representing the number textually (including the exponent part for floats).
Floating point numbers can be converted using exponential notation (4.1E+6).
Arrays are always converted to the string "Array" because of this, echo and print can not by themselves show the contents of an array.
In order to convert objects to string magic method __toString must be used.
Resources are always converted to strings with the structure "Resource id #1", where 1 is the resource number assigned to the resource by PHP at runtime.
Most PHP values can also be converted to strings for permanent storage. This method is called serialization, and is performed by the serialize() function.
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