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title Methods
parent WebView2 Package
nav_order 7

WebView2 Methods Reference

The WebView2 control provides rich methods to control navigation, execute JavaScript, manage resources, etc.

Method List

MoveFocus

Sets focus to the WebView control.

Syntax:

Public Sub MoveFocus()

Example:

WebView21.MoveFocus

Navigate

Navigates to the requested URI. URIs need a protocol prefix, such as http://. Triggers NavigationStarting and NavigationComplete events.

Syntax:

Public Sub Navigate(ByVal uri As String)

Parameters:

  • uri - Target URI

Example:

WebView21.Navigate "https://www.example.com"
' Protocol prefix not required, https:// is added automatically
WebView21.Navigate "www.example.com"

NavigateCustom

Navigates to the requested URI using the specified HTTP method (e.g., GET/POST), optional HTTP headers (vbCrLf separated), and optional POST data. URIs need a protocol prefix, such as http://. Triggers NavigationStarting and NavigationComplete events.

Syntax:

Public Sub NavigateCustom(ByVal uri As String, _
                          method As String, _
                          Optional headers As String, _
                          Optional postData As Variant, _
                          Optional postDataAsUTF8 As Boolean = True)

Parameters:

  • uri - Target URI
  • method - HTTP method (such as "GET", "POST")
  • headers - Optional, HTTP headers (vbCrLf separated)
  • postData - Optional, POST data
  • postDataAsUTF8 - Optional, whether to encode postData as UTF-8 (default True)

Note: Use SupportsNavigateCustomFeatures to check if this feature is supported.

Example:

' POST request
Dim postData As String
postData = "username=admin&password=123456"
WebView21.NavigateCustom "https://api.example.com/login", "POST", _
                        "Content-Type: application/x-www-form-urlencoded", _
                        postData

' GET request with custom headers
WebView21.NavigateCustom "https://api.example.com/data", "GET", _
                        "Authorization: Bearer token123"

NavigateToString

Navigates to the requested HTML string content. Triggers NavigationStarted and NavigationComplete events.

Syntax:

Public Sub NavigateToString(ByVal htmlContent As String)

Parameters:

  • htmlContent - HTML content string

Example:

Dim html As String
html = "<html><body><h1>Hello World</h1></body></html>"
WebView21.NavigateToString html

GoBack

Navigates to the previous URL in the browser navigation history.

Syntax:

Public Sub GoBack()

Example:

If WebView21.CanGoBack Then
    WebView21.GoBack
End If

GoForward

Navigates to the next URL in the browser navigation history.

Syntax:

Public Sub GoForward()

Example:

If WebView21.CanGoForward Then
    WebView21.GoForward
End If

Reload

Reloads the current URL, equivalent to the F5 key.

Syntax:

Public Sub Reload()

Example:

WebView21.Reload

AddObject

Makes a COM object accessible from the JavaScript side via the chrome.webview.hostObjects.ObjName JavaScript syntax.

Syntax:

Public Sub AddObject(ByVal ObjName As String, ByVal Object As Object, ByVal UseDeferredInvoke As Boolean = False)

Parameters:

  • ObjName - Object name to use in JavaScript
  • Object - COM object to expose
  • UseDeferredInvoke - Optional, whether to use deferred invocation (default False)

UseDeferredInvoke Description:

Value Description
False Direct invocation, can return values to JavaScript, but may cause reentrancy issues
True Deferred invocation, avoids reentrancy issues, returns values to JavaScript via Promise asynchronously

See Deferred Callback Mechanism for detailed comparison and use cases of both modes.

Example:

' Add object (default using direct invocation mode)
Set myObject = New MyClass
WebView21.AddObject "MyObject", myObject

' Add deferred invocation mode object (avoids reentrancy issues)
Set dataProcessor = New DataProcessor
WebView21.AddObject "Processor", dataProcessor, True

JavaScript Side Call Example:

// Direct invocation mode (UseDeferredInvoke = False)
const result = chrome.webview.hostObjects.MyObject.GetValue();
console.log(result); // Directly get return value

// Deferred invocation mode (UseDeferredInvoke = True)
chrome.webview.hostObjects.Processor.ProcessData("data").then(
  function (result) {
    console.log("Processing result:", result); // Get return value via Promise
  },
);

// Or use async/await
async function processData() {
  const result = await chrome.webview.hostObjects.Processor.ProcessData("data");
  console.log(result);
}

RemoveObject

Removes a COM object previously exposed via AddObject.

Syntax:

Public Sub RemoveObject(ByVal ObjName As String)

Parameters:

  • ObjName - Object name to remove

Example:

WebView21.RemoveObject "MyObject"

AddScriptToExecuteOnDocumentCreated

Sets JavaScript code to inject into each subsequent navigated webpage. Only takes effect on the next URL navigation.

Syntax:

Public Sub AddScriptToExecuteOnDocumentCreated(ByVal jsCode As String)

Parameters:

  • jsCode - JavaScript code to inject

Example:

' Inject custom script
WebView21.AddScriptToExecuteOnDocumentCreated _
    "window.addEventListener('load', function() {" & vbCrLf & _
    "    console.log('Page loaded!');" & vbCrLf & _
    "});"

AddWebResourceRequestedFilter

Sets a URL filter that will trigger the WebResourceRequested event. Use * and ? for wildcard matching.

Syntax:

Public Sub AddWebResourceRequestedFilter(ByVal sFilter As String, ByVal FilterContext As wv2WebResourceContext)

Parameters:

  • sFilter - URL filter pattern (supports wildcards)
  • FilterContext - Web resource context

Example:

' Intercept all image requests
WebView21.AddWebResourceRequestedFilter "*.jpg", wv2WebResourceContext.wv2Image

' Intercept all requests for a specific domain
WebView21.AddWebResourceRequestedFilter "https://api.example.com/*", wv2WebResourceContext.wv2All

RemoveWebResourceRequestedFilter

Removes a URL filter previously added via AddWebResourceRequestedFilter.

Syntax:

Public Sub RemoveWebResourceRequestedFilter(ByVal sFilter As String, ByVal FilterContext As wv2WebResourceContext)

Parameters:

  • sFilter - URL filter pattern
  • FilterContext - Web resource context

Example:

WebView21.RemoveWebResourceRequestedFilter "*.jpg", wv2WebResourceContext.wv2Image

OpenDevToolsWindow

Opens the Developer Tools window.

Syntax:

Public Sub OpenDevToolsWindow()

Example:

WebView21.OpenDevToolsWindow

CallDevToolsProtocolMethod

Sends a protocol message to the Developer Tools window. If CustomEventId is provided, the DevToolsProtocolResponse event will be triggered with the result.

Syntax:

Public Sub CallDevToolsProtocolMethod(ByVal MethodName As String, _
                                       ByVal ParamsAsJson As String, _
                                       Optional CustomEventId As Variant)

Parameters:

  • MethodName - Method name
  • ParamsAsJson - JSON formatted parameters
  • CustomEventId - Optional, custom event ID

Example:

' Disable script execution
WebView21.CallDevToolsProtocolMethod "Emulation.setScriptExecutionDisabled", "{""value"":true}"

' With custom ID, receive response
WebView21.CallDevToolsProtocolMethod "Runtime.evaluate", "{""expression"":'document.title'}", "MyEventId"

' Handle in event:
Private Sub WebView21_DevToolsProtocolResponse(ByVal CustomEventId As Variant, ByVal JsonResponse As String)
    If CustomEventId = "MyEventId" Then
        Debug.Print JsonResponse
    End If
End Sub

ExecuteScript

Triggers execution of the provided JavaScript code. Does not wait for completion and provides no result.

Syntax:

Public Sub ExecuteScript(ByVal jsCode As String)

Parameters:

  • jsCode - JavaScript code

Example:

WebView21.ExecuteScript "alert('Hello from WebView2!')"

JsRun

Executes the provided JavaScript function with its parameters, waits for completion, and returns the result.

Syntax:

Public Function JsRun(ByVal FuncName As String, ParamArray args() As Variant) As Variant

Parameters:

  • FuncName - JavaScript function name
  • args - Parameter array

Return Value: Return value of the JavaScript function

Example:

' Call simple function
Dim result As Variant
result = WebView21.JsRun("Math.max", 10, 20, 30)
Debug.Print result  ' Output: 30

' Call custom function
WebView21.ExecuteScript "function add(a, b) { return a + b; }"
result = WebView21.JsRun("add", 5, 3)
Debug.Print result  ' Output: 8

' Get page property
result = WebView21.JsProp("document.title")
Debug.Print result  ' Output page title

JsRunAsync

Triggers asynchronous execution of the given JavaScript function with its parameters. Returns a token for identification. When the result arrives, the JsAsyncResult event is triggered (providing the token as one of its parameters).

Syntax:

Public Function JsRunAsync(ByVal FuncName As String, ParamArray args() As Variant) As LongLong

Parameters:

  • FuncName - JavaScript function name
  • args - Parameter array

Return Value: Token used to identify the request

Example:

Dim token As LongLong
token = WebView21.JsRunAsync("fetchData", "https://api.example.com/data")

Private Sub WebView21_JsAsyncResult(ByVal Result As Variant, Token As LongLong, ErrString As String)
    If Token = token Then
        Debug.Print "Result: " & Result
    End If
End Sub

JsProp

Executes the given JavaScript code (e.g., 'document.url'), waits for completion, and returns the result.

Syntax:

Public Function JsProp(ByVal PropName As String) As Variant

Parameters:

  • PropName - JavaScript property or expression

Return Value: Property value or expression result

Example:

Dim url As String
url = WebView21.JsProp("document.URL")
Debug.Print url

Dim title As String
title = WebView21.JsProp("document.title")
Debug.Print title

Dim scrollPos As Long
scrollPos = WebView21.JsProp("window.scrollY")
Debug.Print scrollPos

PostWebMessage

Sends a message to the JavaScript side, which can be received via window.chrome.webview.addEventListener('message', handler). Requires IsWebMessageEnabled to be set to True.

Syntax:

Public Sub PostWebMessage(Message As Variant)

Parameters:

  • Message - Message to send (can be a string or other type, non-string types are automatically converted to JSON)

Description:

  • If Message is a string type, use PostWebMessageAsString to send the raw string
  • If Message is another type (including objects), use PostWebMessageAsJson to automatically convert to JSON

Example:

' Send string
WebView21.PostWebMessage "Hello from VB6"

' Send object (automatically converted to JSON)
Dim dict As Object
Set dict = CreateObject("Scripting.Dictionary")
dict("type") = "notification"
dict("message") = "Data updated"
dict("timestamp") = CLng(Now)
WebView21.PostWebMessage dict

' JavaScript side receive:
// window.chrome.webview.addEventListener('message', (event) => {
//     console.log(event.data);
//     // String: "Hello from VB6"
//     // Object: {type: "notification", message: "Data updated", timestamp: ...}
// });

// Or use async/await to receive messages
// window.chrome.webview.addEventListener('message', async (event) => {
//     const data = event.data;
//     if (typeof data === 'string') {
//         console.log('String:', data);
//     } else {
//         console.log('Object:', data.type, data.message);
//     }
// });

PostWebMessageJSON

Sends raw JSON value to the JavaScript side, which can be received via window.chrome.webview.addEventListener('message', handler). Requires IsWebMessageEnabled to be set to True.

Syntax:

Public Sub PostWebMessageJSON(jsonString As String)

Parameters:

  • jsonString - JSON formatted string

Example:

WebView21.PostWebMessageJSON "{""type"":""alert"",""message"":""Hello""}"

Suspend

Suspends WebView2 processing/rendering. Useful for creating tabs. Use SupportsSuspendResumeFeatures to check if this feature is supported.

Syntax:

Public Sub Suspend()

Example:

If WebView21.SupportsSuspendResumeFeatures Then
    WebView21.Suspend
End If

Private Sub WebView21_SuspendCompleted()
    Debug.Print "WebView suspended successfully"
End Sub

Resume

Resumes WebView2 processing/rendering after a previous Suspend call. Use SupportsSuspendResumeFeatures to check if this feature is supported.

Syntax:

Public Sub Resume()

Example:

If WebView21.SupportsSuspendResumeFeatures Then
    WebView21.Resume
End If

SetVirtualHostNameToFolderMapping

Creates a virtual mapping of the specified hostname to a local folder. Use SupportsFolderMappingFeatures to check if this feature is supported.

Note: Due to a WebView2 bug, this may cause a 2-second delay in name resolution if you're not careful with the hostname selection. See MicrosoftEdge/WebView2Feedback#2381

Syntax:

Public Sub SetVirtualHostNameToFolderMapping(ByVal hostName As String, _
                                               ByVal folderPath As String, _
                                               ByVal accessKind As wv2HostResourceAccessKind = wv2HostResourceAccessKind.wv2ResourceAllow)

Parameters:

  • hostName - Virtual hostname
  • folderPath - Local folder path
  • accessKind - Access type (default wv2ResourceAllow)

Example:

' Map local folder as virtual domain
WebView21.SetVirtualHostNameToFolderMapping "app.local", "C:\MyApp\wwwroot"

' Now can access local files
WebView21.Navigate "https://app.local/index.html"

ClearVirtualHostNameToFolderMapping

Removes the virtual mapping of the specified hostname previously set via SetVirtualHostNameToFolderMapping. Use SupportsFolderMappingFeatures to check if this feature is supported.

Syntax:

Public Sub ClearVirtualHostNameToFolderMapping(ByVal hostName As String)

Parameters:

  • hostName - Hostname to clear

Example:

WebView21.ClearVirtualHostNameToFolderMapping "app.local"

PrintToPdf

Saves the current document as a PDF file. Use SupportsPdfFeatures to check if this feature is supported.

Syntax:

Public Sub PrintToPdf(ByVal outputPath As String, _
                      Optional ByVal Orientation As wv2PrintOrientation = wv2PrintOrientation.wv2PrintPortrait, _
                      Optional ByVal ScaleFactor As Variant, _
                      Optional PageWidth As Variant, _
                      Optional PageHeight As Variant, _
                      Optional ByVal MarginTop As Variant, _
                      Optional ByVal MarginBottom As Variant, _
                      Optional ByVal MarginLeft As Variant, _
                      Optional ByVal MarginRight As Variant, _
                      Optional ByVal ShouldPrintBackgrounds As Boolean = False, _
                      Optional ByVal ShouldPrintSelectionOnly As Boolean = False, _
                      Optional ByVal ShouldPrintHeaderAndFooter As Boolean = True, _
                      Optional ByVal HeaderTitle As Variant, _
                      Optional ByVal FooterUri As Variant)

Parameters:

  • outputPath - Output PDF file path
  • Orientation - Optional, page orientation (default portrait)
  • ScaleFactor - Optional, scale factor
  • PageWidth - Optional, page width
  • PageHeight - Optional, page height
  • MarginTop - Optional, top margin
  • MarginBottom - Optional, bottom margin
  • MarginLeft - Optional, left margin
  • MarginRight - Optional, right margin
  • ShouldPrintBackgrounds - Optional, whether to print backgrounds (default False)
  • ShouldPrintSelectionOnly - Optional, whether to print only selected content (default False)
  • ShouldPrintHeaderAndFooter - Optional, whether to print header and footer (default True)
  • HeaderTitle - Optional, header title
  • FooterUri - Optional, footer URI

Example:

' Basic print
WebView21.PrintToPdf "C:\output.pdf"

' Print landscape with backgrounds
WebView21.PrintToPdf "C:\output.pdf", wv2PrintOrientation.wv2PrintLandscape, , , , , , , , True

' Full configuration
WebView21.PrintToPdf "C:\output.pdf", _
                   wv2PrintOrientation.wv2PrintPortrait, _
                   1.0, _
                   210, _
                   297, _
                   10, _
                   10, _
                   10, _
                   10, _
                   True, _
                   False, _
                   True, _
                   "My Document", _
                   "https://www.example.com"

Private Sub WebView21_PrintToPdfCompleted()
    MsgBox "PDF saved successfully!"
End Sub

OpenDefaultDownloadDialog

Opens the built-in download manager dialog. Use SupportsDownloadDialogFeatures to check if this feature is supported.

Syntax:

Public Sub OpenDefaultDownloadDialog()

Example:

WebView21.OpenDefaultDownloadDialog

CloseDefaultDownloadDialog

Closes the built-in download manager dialog. Use SupportsDownloadDialogFeatures to check if this feature is supported.

Syntax:

Public Sub CloseDefaultDownloadDialog()

Example:

WebView21.CloseDefaultDownloadDialog

OpenTaskManagerWindow

Opens the built-in task manager dialog. Use SupportsTaskManagerFeatures to check if this feature is supported.

Syntax:

Public Sub OpenTaskManagerWindow()

Example:

WebView21.OpenTaskManagerWindow

Usage Examples

Complete Navigation Example

Private Sub cmdGo_Click()
    WebView21.Navigate txtURL.Text
End Sub

Private Sub cmdBack_Click()
    If WebView21.CanGoBack Then
        WebView21.GoBack
    End If
End Sub

Private Sub cmdForward_Click()
    If WebView21.CanGoForward Then
        WebView21.GoForward
    End If
End Sub

Private Sub cmdReload_Click()
    WebView21.Reload
End Sub

JavaScript Interaction Example

' Synchronous call
Dim title As String
title = WebView21.JsProp("document.title")
Me.Caption = title

' Call function
Dim result As Variant
result = WebView21.JsRun("parseInt", "12345")
Debug.Print result

' Asynchronous call
Dim token As LongLong
token = WebView21.JsRunAsync("fetchData", "api/data")

Download Management Example

Private Sub WebView21_DownloadStarting(ByRef ResultFilePath As String, _
                                      ByRef Cancel As Boolean, _
                                      ByRef Handled As Boolean)
    ' Change download location
    ResultFilePath = "C:\Downloads\" & Mid(ResultFilePath, InStrRev(ResultFilePath, "\") + 1)
    Handled = True
End Sub

Private Sub cmdOpenDownloads_Click()
    WebView21.OpenDefaultDownloadDialog
End Sub

PDF Export Example

Private Sub cmdExportPDF_Click()
    If WebView21.SupportsPdfFeatures Then
        Dim outputPath As String
        outputPath = "C:\Documents\" & WebView21.DocumentTitle & ".pdf"
        WebView21.PrintToPdf outputPath, , , , , , , , , True
    Else
        MsgBox "PDF export not supported"
    End If
End Sub