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javascriptprototype

How to tell if an object has a given prototype?

How can one detect if a given browser has the searchParams prototype for URL? https://developer.mozilla.org/en-US/docs/Web/API/URL/searchParams states that Chrome and FF do but Edge does not, but I wish to detect using JavaScript.

I've messed around with isPrototypeOf, but don't think it is applicable.

Solution

  • In supporting browsers, there will be an URLSearchParams constructor available on global object, so like any other global Constructor, 

    'URLSearchParams' in window

    or 

    typeof window.URLSearchParams === 'function'

    and alike will do.

    const support = typeof window.URLSearchParams === 'function';
console.log('supports URLSearchParams API:', support);

var url = new URL('https://stackoverflow.com/questions/47824782/how-to-tell-if-an-object-has-a-given-prototype?support="true"');
if(support){
    console.log(url.searchParams.get('support'));
}