How to query data type in php?-PHP Problem-php.cn

How to query the data type in php: 1. Use "gettype (pass in a variable var)" to display the type of variable var; 2. Use "var_dump (pass in a variable var)" to display the variable var type; 3. Use the "is_*" series of functions to determine whether the variable is of the specified type, and return true if so.

How to query data type in php?

Recommended: "PHP Video Tutorial"

View data types

gettype(pass in a variable) can get the type of the variable
var_dump(pass in a variable) output the variable type and value


        
         Copy after login

Judge data type

We use the is_* series of functions. The is_types series of functions are used to determine whether something is of a certain type. Returns true if it is of this type, false if it is not.

Function	Analysis
is_int	is Integer
is_bool	Is it a Boolean
is_float	Is it a floating point
is_string	Is it a string
is_array	Is it an array
is_object	Is it an object
is_null	Is it empty
is_resource	Is it a resource
is_scalar	Is it a scalar
is_numeric	Is it Is the numeric type
is_callable	Is it a function


        
         Copy after login

Note: istypes is easy to remember. Just follow the type before and after is.

Scalar: int, float, bool, string

Mixed types: array, object

Special types: null, resource, callback

Why did echo execute a false interval in the final experiment?
Answer: Because echo is not a function, it is basic syntax. You don’t need to understand the difference between functions and basic syntax right now. Understanding and not understanding have no impact in actual development. Just know that you have this knowledge.

For more programming-related knowledge, please visit:Introduction to Programming! !

The above is the detailed content of How to query data type in php?. For more information, please follow other related articles on the PHP Chinese website!