PHP Data-type conversions and operator expressions

One: Conversion of data types
Get type:
GetType ($a);
Determine if there is some type of data:
Is_ type name ($a);

1. (int) $a;
2.settype ($a, int);

Two: operator expressions

1. Mathematical operators
/except: integer In addition to integer result is decimal (reason: PHP is a weakly typed language)

2. String: Stitching a string with a dot (.) is not used (+)

3. Comparison operators: Same

4. Logical operator:&& with available and | | Available or

PHP Data-type conversions and operator expressions