Answer: Use the typeof operator If you want to check whether a variable has been initialized or defined (i.e. test whether a variable has been declared and assigned a value) you can use the typeof operator.
How do you check if a variable has been initialized?
Answer: Use the typeof operator If you want to check whether a variable has been initialized or defined (i.e. test whether a variable has been declared and assigned a value) you can use the typeof operator.