Browser

Overview

Browser is a singleton (new BrowserManager()) exported from @bitrix24/b24jssdk. It bundles cheap user-agent / platform / capability checks the SDK relies on internally and exposes them for application code:

• Browser detection — Opera, Internet Explorer (6 through 11, plus a numeric detectIEVersion), Safari, Firefox, Chrome.
• OS / platform detection — macOS, Windows, Linux, Android (with detectAndroidVersion), iPad, iPhone, and a combined isIOS.
• Capabilities — isMobile, isRetina, isTouchDevice, isDoctype, and isLocalStorageSupported.

All checks are derived from a module-level UA string — a lower-cased navigator.userAgent captured once at import time — or from browser globals (window, document, navigator, localStorage). Because of this, Browser is only meaningful in a browser context.

import { Browser } from '@bitrix24/b24jssdk'

if (Browser.isMobile()) {
  // ...
}

if (Browser.isLocalStorageSupported()) {
  // ...
}

Method Signature

Browser detection

isOpera(): boolean                           // UA includes 'opera'
isIE(): boolean                              // legacy 'attachEvent' in document, and not Opera
isIE6(): boolean                             // UA includes 'msie 6'
isIE7(): boolean                             // UA includes 'msie 7'
isIE8(): boolean                             // UA includes 'msie 8'
isIE9(): boolean                             // document.documentMode >= 9
isIE10(): boolean                            // document.documentMode >= 10
isIE11(): boolean                            // detectIEVersion() >= 11
detectIEVersion(): number                    // numeric IE version, -1 if not IE
isSafari(): boolean                          // UA includes 'safari' and not 'chrome'
isFirefox(): boolean                         // UA includes 'firefox'
isChrome(): boolean                          // UA includes 'chrome'

OS / platform detection

isMac(): boolean                             // UA includes 'macintosh'
isWin(): boolean                             // UA includes 'windows'
isLinux(): boolean                           // UA includes 'linux', and not Android
isAndroid(): boolean                         // UA includes 'android'
detectAndroidVersion(): number               // parsed Android version, 0 if not detected
isIPad(): boolean                            // UA includes 'ipad;', or Mac + touch
isIPhone(): boolean                          // UA includes 'iphone;'
isIOS(): boolean                             // isIPad() || isIPhone()

Capabilities

isMobile(): boolean                          // iPhone / iPad / Android / 'mobile' / 'touch' UA
isRetina(): boolean                          // window.devicePixelRatio >= 2
isTouchDevice(): boolean                     // 'ontouchstart' in window, or maxTouchPoints > 0
isDoctype(target?: any): boolean             // compatMode === 'CSS1Compat' (or fallback)
isLocalStorageSupported(): boolean           // setItem/removeItem round-trip succeeds

Key Concepts

• isIPad() covers modern iPadOS. Since iPadOS reports itself as macOS in the UA string, isIPad() also returns true for a Mac-flavoured UA that also reports touch support (isTouchDevice()), which is how it distinguishes an iPad from a real desktop Mac.
• detectIEVersion() returns -1 for non-IE browsers. It short-circuits to -1 for Opera, Safari, Firefox, and Chrome before running the IE/Trident-specific heuristics, so it is safe to call unconditionally.
• isDoctype(target?) accepts any document-like object. Pass an iframe's document (or similar) to check its rendering mode instead of the top-level page; omitting target falls back to the global document.
• isLocalStorageSupported() is a real write/remove probe, not just a typeof localStorage check — it also catches cases where the API exists but throws (private browsing modes, storage quota exhausted, disabled by policy).

Error Handling

Browser is designed for browser runtimes. The module-level user-agent read and isLocalStorageSupported() are wrapped in try/catch, but most checks dereference document / window / navigator directly (for example isIE, isIE9, isRetina, isTouchDevice, detectIEVersion, detectAndroidVersion) and throw a ReferenceError when those globals are absent. Guard any call behind an environment check (or avoid Browser entirely) in Node.js / SSR code paths that may execute before hydration.

Examples

Browser detection:

import { Browser } from '@bitrix24/b24jssdk'

if (Browser.isChrome()) {
  // Chrome-specific behaviour
}

if (Browser.isIE()) {
  const version = Browser.detectIEVersion()
  console.log(`Running on Internet Explorer ${version}`)
}

OS / platform branching:

import { Browser } from '@bitrix24/b24jssdk'

if (Browser.isIOS()) {
  // Shared iPhone / iPad branch
}

if (Browser.isAndroid()) {
  const version = Browser.detectAndroidVersion()
  console.log(`Android version: ${version}`)
}

Capability checks:

import { Browser } from '@bitrix24/b24jssdk'

if (Browser.isMobile() && Browser.isTouchDevice()) {
  // Adjust layout / hit-targets for touch
}

if (Browser.isRetina()) {
  // Serve high-resolution assets
}

Guarding localStorage access and checking a document's rendering mode:

import { Browser } from '@bitrix24/b24jssdk'

function persist(key: string, value: string): void {
  if (!Browser.isLocalStorageSupported()) {
    return
  }

  localStorage.setItem(key, value)
}

if (!Browser.isDoctype(document)) {
  console.warn('Page is rendered in quirks mode')
}

Alternatives and Recommendations

• Prefer feature detection over UA sniffing when possible. Browser's checks are heuristics based on navigator.userAgent, which can be spoofed, frozen, or reduced by the browser. For example, prefer checking 'ontouchstart' in window directly (or Browser.isTouchDevice(), which does exactly that) over inferring touch support from platform checks.
• Use isMobile() / isTouchDevice() for layout decisions, not for gating functionality. Treat them as UX hints (e.g. bigger tap targets, simplified navigation) rather than as a way to disable features outright — a desktop browser in a touch-enabled laptop is a legitimate combination.
• The IE-related methods (isIE*, detectIEVersion, isIE11) target long-retired browsers. Keep them only for legacy compatibility branches; new code targeting current browsers generally does not need them.
• Runtime type checks for values (not the environment) live in Type. Browser answers "what am I running in", while Type answers "what shape is this value".