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(1) The class modules (two class modules starting with "BiDi") containing the WinHttp API functions required to use WebSocket communication from VBA and usability wrappers. Import these into the SeleniumVBA file you wish to operate.
(2) Add the following description to the main routine of your standard module. That is all. Introduction has become significantly easier from ver. 7.2.
Dim driver As WebDriver: Set driver = New WebDriver
With driver
' Start
.StartChrome
' Browser startup settings (for both Chrome and Edge)
Dim caps As WebCapabilities: Set caps = .CreateCapabilities
caps.EnableBiDiMode 'WebDriver BiDi becomes enabled
' Open
.OpenBrowser caps
' Perform WebSocket communication to use WebDriver BiDi
Dim bidi As New BiDiCommandWrapper: bidi.ConnectTo .GetWebSocketUrl
'Typing "bidi." will display BiDi-specific methods
bidi.
(3) Set the VBE error trapping to "Break on Unhandled Errors."
In this article, I will introduce particularly powerful and practical major methods from the VBA class BiDiCommandWrapper, which fuses the WebDriver BiDi protocol and CDP (Chrome DevTools Protocol).
| Category | Method Name | Overview (Detailed Version) |
|---|---|---|
| Navigation | ExecuteNavigateAndGetStatus |
Checks HTTP status after URL transition. An SPA synchronization engine waits until communication (Net) and rendering (DOM) stop, suppressing errors immediately after transition. |
| Element Operation | ExecuteClickByXPath |
Scrolls into the display area, focuses, and clicks. It automatically waits for communication to stabilize after the action, enabling extremely stable operation. |
ExecuteInputValueByXPath |
Simulates input using execCommand. This ensures state updates in React, etc., solving the problem where values are not reflected. |
|
ExecuteSelectValueByXPath |
Dropdown operation. Allows selection by display text as well as Value. It forcibly triggers events after selection to ensure display changes are triggered. | |
ExecuteRegisterAutoClickerByXPath |
Utilizes CDP to station a "silent observer" inside the browser. Clicks elements the millisecond they appear without waiting for VBA communication. Perfect for conquering high-speed SPA redirects or transient pop-ups. | |
| Special/Hierarchical | GetIframeContextIdByUrl |
Identifies iframe by URL. By passing the obtained ID to other methods, you can operate directly inside the frame without using SwitchTo. |
ExecuteShadowClick |
Recursively searches and penetrates hidden Shadow DOM using an array of CSS selectors. Conquers modern sites with Web Components structures. | |
| Management/Optimization | ExecuteEnableResourceBlocking |
Blocks the loading of images, ads, etc. Minimizes network load and dramatically improves execution speed. |
ExecuteWebExtensionInstall |
Installs Chrome extensions instantly. Allows dynamic integration of ad blockers or custom tools to extend browser functionality via program. | |
| AI Collaboration | StartDiscoveryLog |
Records internal browser communication, errors, and DOM changes in detail. Outputs "AI-Ready" logs that LLMs like Gemini can use to diagnose causes instantly. |
Navigates to the specified URL and returns success/failure (e.g., 200: Success, 500: Failure) based on the HTTP status code. The internal SPA synchronization engine, which waits until both "network communication" and "DOM changes" stop, dramatically suppresses element-not-found errors immediately after navigation.
- targetUrl (String): Destination URL.
- waitNetworkIdle (Boolean): Whether to wait until communication and DOM are completely stationary (Default: True).
- contextId (String): Used to specify a target tab or frame.
Dim status As Long
status = bidi.ExecuteNavigateAndGetStatus("[https://example.com/dashboard](https://example.com/dashboard)")
If status = 200 Then Debug.Print "Transition and SPA rendering successful"Ensures execution in the order of "Auto-scroll to view" → "Focus" → "Click". Because it automatically performs synchronous waiting until any asynchronous communication triggered by the operation ends, extremely stable continuous operation is possible.
- path (String): XPath to identify the target element.
- searchTimeoutMs (Long): Maximum wait time for the element to appear (milliseconds).
- waitNetworkIdle (Boolean): Whether to wait for communication updates after clicking.
' Reliable click including scroll and communication wait
bidi.ExecuteClickByXPath "//button[@id='submit-order']"By internally utilizing JavaScript's execCommand('insertText'), it generates events equivalent to a human typing on a keyboard. This solves the issue where frameworks like React or Vue do not recognize simple .value overwrites (internal state is not updated).
' Input that ensures validation in React, etc. is triggered
bidi.ExecuteInputValueByXPath "//input[@id='username']", "vba_user"Operates a dropdown (select element). Items can be selected not only by the internal Value but also by the text visible on the screen. It automatically triggers necessary events after selection.
' Select item by displayed text (March 2026)
bidi.ExecuteSelectValueByXPath "//select[@name='calselect']", "2026年03月", TrueRegisters a persistent JavaScript-based MutationObserver via the CDP command Page.addScriptToEvaluateOnNewDocument. This script is injected and executed every time a new document or frame is initialized, even before the VBA code has a chance to send a "Find Element" command.
' Example: Handle a "Save Successful" popup that might appear after any action
bidi.ExecuteRegisterAutoClickerByXPath "//button[text()='Dismiss']"
' Proceed with standard automation without worrying about the popup timing
bidi.ExecuteClickByXPath "//input[@id='save-records']"Penetrates and clicks through Shadow DOM (encapsulated internal structures) that cannot be reached by normal XPath searches. You pass an array of CSS selectors required to reach the target as an argument.
' Follow the Shadow Hosts in order to specify the final button
Dim path(2) As String
path(0) = "settings-ui" ' 1st host
path(1) = "settings-main" ' 2nd host
path(2) = "#confirm-button" ' Final target
bidi.ExecuteShadowClick pathIdentifies an iframe by a part of its URL and obtains an operation ID (contextId). By passing this ID to the contextId argument of any other method, you can operate directly within that frame.
Dim conID As String: conID = bidi.GetIframeContextIdByUrl("login_frame")
' Click an element inside the frame by specifying the ID
bidi.ExecuteClickByXPath "//button[@id='submit']", , , , , conIDBlocks images, ads, tracking communications, etc., at the browser level. By eliminating unnecessary communication, execution speed is dramatically improved.
' Accelerate by blocking images and ad domains
Dim blockList: blockList = Array("*.png", "*.jpg", "*google-analytics.com*", "*doubleclick*")
bidi.ExecuteEnableResourceBlocking blockListInstalls a Chrome extension from the specified path into the current browser session. This allows for dynamic integration of ad blockers, security enhancements, or specific business auxiliary tools within the automation process.
- extensionPath (String): File path to the extension.
' Settings to enable Chrome extensions
caps.AddArguments "--remote-debugging-pipe"
caps.AddArguments "--enable-unsafe-extension-debugging"
' Dynamically load Chrome extension and start scraping in a clean environment
bidi.ExecuteWebExtensionInstall Environ("LOCALAPPDATA") & "\Google\Chrome\User Data\Default\Extensions\aapbdbdomjkkjkaonfhkkikfgjllcleb\2.0.16_0"Records events occurring inside the browser in an "AI-decipherable format." By feeding the saved logs to Gemini or ChatGPT, you can achieve "AI-Ready" debugging where error causes are automatically diagnosed.
' Start log recording (excluding noisy image/CSS logs)
bidi.StartDiscoveryLog excludeImagesAndCss:=True
' (Execute operations...)
' Save the log. Passing this to AI completes the debugging.
bidi.StopAndSaveDiscoveryLog "C:\temp\discovery_log.txt"Based on experiments with the following code, I confirmed that WebDriver BiDi can be enabled and events can be detected even from an already launched instance of Edge.
'=================================================
' Automatically operate a browser in a logged-in state via remote debugging.
' Start from an already launched state via a shortcut.
'=================================================
' Set the shortcut target as follows:
' "C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe" --remote-debugging-port=9222 --user-data-dir="C:\EdgeDebugProfile"
'=================================================
Dim caps As SeleniumVBA.WebCapabilities
Set driver = SeleniumVBA.New_WebDriver
driver.StartEdge
Set caps = driver.CreateCapabilities(initializeFromSettingsFile:=False)
caps.SetDebuggerAddress "localhost:9222"
'Enable BiDi (Required to be True for this program)
caps.EnableBiDiMode
driver.OpenBrowser caps
' (Continued...)In the BiDiCommandWrapper class, we adopt a strategy of "delegating to JavaScript" via script.callFunction rather than firing repetitive, native BiDi commands.
This approach compensates for VBA’s single-threaded nature and minimizes communication overhead. Below are the three primary advantages of offloading processing to JavaScript.
The greatest challenge in VBA automation is the "Excel is not responding" state caused by synchronous communication latency. A typical sequence—Find Element → Get Coordinates → Scroll → Click—requires at least four round-trips if executed using individual BiDi commands.
By wrapping this logic into a single JavaScript snippet and sending it via script.callFunction, the entire process is completed internally by the browser. VBA only needs to send one command and wait for a single "success" response, significantly reducing the risk of UI freezing.
The raw data returned by WebDriver BiDi often consists of deeply nested and complex JSON structures. Parsing these in VBA is CPU-intensive and leads to overly complicated code.
To avoid this, we let the JavaScript side process the data and return a simplified string, such as JSON.stringify({status: 'ok', value: isVisible}). Consequently, the VBA side only needs to handle a simple string—often using basic regular expressions—making the overall processing remarkably lightweight.
The current WebDriver BiDi specification is still evolving and lacks high-level features that are essential for stable automation, such as "Is the element visible to the user?" (Visibility) or "Has network activity ceased?" (Network Idle).
Advanced monitoring—such as using MutationObserver to track DOM changes or hooking into fetch/XHR to monitor traffic—can only be performed by JavaScript within the browser context. We utilize BiDi primarily as a "high-speed tunnel" to inject JavaScript, allowing the browser’s native capabilities to handle the complex logic.
By offloading logic to JavaScript, SeleniumVBA remains shielded from communication bottlenecks and complex parsing logic. This ensures a stable, responsive, and robust browser control experience within the VBA environment.