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JavaScript JavaScript Foundations Functions Return Values

Richard Zili
Richard Zili
6,451 Points
Posted by Richard Zili
Richard Zili
6,451 Points

In an array, how does one pass a value of "string" or "number" without actually specifying a string or number?

This is in regards to the code challenge in the "Return Values" section of the JavaScript lessons

3 Answers

Kristen Law
Kristen Law
16,244 Points

To get the value type of a variable, you would use the typeof operator before the variable.

Within your function, you want to find the value type of the parameter that is passed into it, so you would use typeof parameter_variable and then check to see if it is equal to 'string', 'number', or 'undefined'.

See below:

function arrayCounter(array){
      if (typeof array === 'string' || typeof array === 'number' || typeof array === 'undefined'){
          return 0;
      }
      return array.length;
  }
Richard Zili
Richard Zili
6,451 Points
Richard Zili
Richard Zili
6,451 Points

Thanks for your help!

Yannis Antonopoulos
PLUS
Yannis Antonopoulos
Courses Plus Student 1,372 Points
Yannis Antonopoulos
Yannis Antonopoulos
Courses Plus Student 1,372 Points

Thanks also by me!

Jose Guerra
PLUS
Jose Guerra
Courses Plus Student 9,338 Points
Jose Guerra
Jose Guerra
Courses Plus Student 9,338 Points

thanks :D