Settype for changing types in PHP - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the settype() function do in PHP?

The settype() function changes the type of a variable to a specified type, like integer, string, or boolean.

beginner

How do you change a variable $var to an integer using settype()?

Use settype($var, 'integer'); to convert $var to an integer type.

intermediate

What types can you use with settype()?

You can use types like 'boolean', 'bool', 'integer', 'int', 'float', 'double', 'string', 'array', and 'object'.

intermediate

Does settype() return the converted value or something else?

settype() returns true on success and false on failure. It changes the variable itself by reference.

advanced

What happens if you try to convert a string like '123abc' to an integer using settype()?

PHP converts the string to the integer 123, stopping at the first non-numeric character.

What is the correct way to change a variable $x to a boolean using settype()?

A settype($x, 'boolean');

B settype($x, 'bool');

C settype($x, 'boolean_value');

D settype($x, 'boolean()');

Both 'boolean' and 'bool' are valid type names accepted by settype().

What does settype() return after converting a variable?

A True on success, false on failure

B Nothing (void)

C The old value of the variable

D The new value of the variable

settype() returns true if the conversion worked, false otherwise.

Which of these is NOT a valid type for settype()?

A integer

B string

C number

D array

'number' is not a valid type name for settype(). Use 'integer' or 'float' instead.

If $var = '45.67', what will settype($var, 'integer') do?

A $var becomes 45

B $var becomes 45.67

C $var becomes 0

D Conversion fails

When converting a float string to integer, PHP takes the integer part only.

Can settype() convert a variable to an object?

A No

B Only if the variable is a string

C Only if the variable is an array

D Yes

You can convert variables to objects using settype('object').

Explain how settype() changes the type of a variable in PHP.

Think about how PHP handles variable types and what settype() does to the variable itself.

Describe what happens when you convert a string with numbers and letters (e.g., '123abc') to an integer using settype().

Consider how PHP reads strings when converting to numbers.