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JavaScript JavaScript Foundations Functions Return Values

Jason Nelson
Jason Nelson
9,127 Points
Posted by Jason Nelson
Jason Nelson
9,127 Points

problems with function if statements

I'm having a issue with function challenge state 5. It's asking to return the Array length if passed in parameter is an array. Otherwise, if it's a string, undefined, or number to return 0. I get one of two errors, either it says I'm missing the function arrayCounter or it says gets 0 when the array 1,2,3 is passed in.

Here are some solutions I have tried

function arrayCounter (x) { if (x === 'array') { return array.length; } if (x === 'string', 'undefined', 'number') { return 0; } };

function arrayCounter (array) { if (typeOf x === 'array') { return array.length; } if (typeOf x === 'number', 'string', 'undefined') { return 0; } };

2 Answers

Curtis Schrum
Curtis Schrum
10,174 Points
Curtis Schrum
Curtis Schrum
10,174 Points

Yeah I love the course I do but honestly TypeOf is terrible for finding out if something is an array. Without seeing all the code I can give you an idea of how to find out of its an array. Using variable X

if (x.isArray){
//Do stuff here

}else if (typeof x === 'number'){
//do stuff here if number

}else if(typeof x === 'string'){
//do stuff here if string

}else{
//final catch all
}

See if that helps

Jason Nelson
Jason Nelson
9,127 Points
Jason Nelson
Jason Nelson
9,127 Points

Awesome! Got it to work with your solution.

Jason Nelson
Jason Nelson
9,127 Points
Jason Nelson
Jason Nelson
9,127 Points

I tried this and still no luck..

<!DOCTYPE html> <html lang="en"> <head> <title>JavaScript Foundations: Functions</title> <style> html { background: #FAFAFA; font-family: sans-serif; } </style> </head> <body> <h1>JavaScript Foundations</h1> <h2>Functions: Return Values</h2> <script>

 function arrayCounter(x) {
        if (x.isArray) {
            return x.length;
     }else if 
    (typeof x === 'string' || 'number' || 'undefined') {
            return 0;

    }
}


</script>

</body> </html>

Curtis Schrum
Curtis Schrum
10,174 Points

Yeah your right for whatever reason isArray is not working. So I went in and solved it, I had to use instanceof which I personally consider a back practice I also had to break up the if statement into multiple lines putting them all in the way I wanted which was using != was not working either. Below is the solution

function arrayCounter(x){

        if(typeof x == 'undefined'){
          return 0;
        }else if (typeof x == 'string'){
          return 0;
        }else if (typeof x == 'number'){
          return 0;
        }else if (x instanceof Array){
          return x.length;
        }
      }