ベンダープレフィックス決めるくん.js

detectVendorFunction.js

function detectVendorFunction(object, methodName) {
  var upperName = methodName.charAt(0).toUpperCase()+methodName.substr(1),
      detectedMethod;

  detectedMethod = object[methodName] ||
                   object['webkit'+upperName] ||
                   object['moz'+upperName] ||
                   object['ms'+upperName] ||
                   object['o'+upperName];

  if (detectedMethod) {
    return detectedMethod;
  } else {
    throw new Error(methodName+' not found in specified object');
  }
}

var getUserMedia = detectVendorFunction(navigator, 'getUserMedia');

var requestAnimationFrame = detectVendorFunction(window, 'requestAnimationFrame');