How can I tell if a parameter passed to a function is an object or a string?

Question

I have this function:

error = (error, modelState, modalHeader, modalBody): ng.IPromise<any> => {
    // function code here

In some cases the first parameter could be a string such as:

"problem"

in other cases it could be an object such as this:

{
"ErrorMessage":"END_TEST - Invalid TestID, Unauthorized Access or TestStatus is not Started or Paused",
"ErrorNumber":50001
}

Is there a way that I could detect if it is a string or an object?

http://stackoverflow.com/questions/7390426/better-way-to-get-type-of-a-javascript-variable — Dmitrii Zyrianov, Feb 28 '16 at 11:13
Can you give an example of how the typeof could be used for this so I can make the question as answered. — Alan2, Feb 28 '16 at 11:52

score 1 · Accepted Answer · answered Feb 28 '16 at 11:12

typeof operator is your friend:

error = (error, modelState, modalHeader, modalBody): ng.IPromise<any> => {
   if (typeof error === 'string') {
     //string
   } else if (typeof error === 'object') {
     //object
   }
}

typeof can evaluate to following: string, number, object, undefined, boolean, function.

How can I tell if a parameter passed to a function is an object or a string?

1 Answers1