UserConsentVerifier Class

Reference

Definition

Namespace:: Windows.Security.Credentials.UI

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Edit

Checks for availability of a verification device (such as a Microsoft Passport PIN, Windows Hello biometric, or fingerprint reader), and performs a verification.

public ref class UserConsentVerifier abstract sealed

/// [Windows.Foundation.Metadata.ContractVersion(Windows.Foundation.UniversalApiContract, 65536)]
/// [Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
/// [Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
class UserConsentVerifier final

[Windows.Foundation.Metadata.ContractVersion(typeof(Windows.Foundation.UniversalApiContract), 65536)]
[Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
[Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
public static class UserConsentVerifier

Public Class UserConsentVerifier

Inheritance: Object Platform::Object IInspectable UserConsentVerifier

Attributes: ContractVersionAttribute MarshalingBehaviorAttribute ThreadingAttribute

Windows requirements

Device family	Windows 10 (introduced in 10.0.10240.0)
API contract	Windows.Foundation.UniversalApiContract (introduced in v1.0)

Examples

Desktop apps using C#

For a desktop app, instead of calling the UserConsentVerifier.RequestVerificationAsync method, you'll need to:

First Retrieve a window handle (HWND). That topic contains code examples for Windows UI Library (WinUI) 3, Windows Presentation Foundation (WPF), and Windows Forms (WinForms). Plug that code into the code listing below.
Then call the RequestVerificationForWindowAsync method of the Windows.Security.Credentials.UI.UserConsentVerifierInterop C# interop class. For more info about the C# interop classes, see Call interop APIs from a .NET app. Also see Display WinRT UI objects that depend on CoreWindow.

private async System.Threading.Tasks.Task<string> RequestConsent(string userMessage)
{
    string returnMessage;

    if (String.IsNullOrEmpty(userMessage))
    {
        userMessage = "Please provide fingerprint verification.";
    }

    try
    {
        // Retrieve the window handle by passing a reference to the WinUI 3 window object 
        var hwnd = ...
        // Request the logged on user's consent via fingerprint swipe using the interop interface
        var consentResult = await Windows.Security.Credentials.UI.UserConsentVerifierInterop.RequestVerificationForWindowAsync(hwnd, userMessage);

        switch (consentResult)
        {
            case Windows.Security.Credentials.UI.UserConsentVerificationResult.Verified:
                returnMessage = "Fingerprint verified.";
                break;
            case Windows.Security.Credentials.UI.UserConsentVerificationResult.DeviceBusy:
                returnMessage = "Biometric device is busy.";
                break;
            case Windows.Security.Credentials.UI.UserConsentVerificationResult.DeviceNotPresent:
                returnMessage = "No biometric device found.";
                break;
            case Windows.Security.Credentials.UI.UserConsentVerificationResult.DisabledByPolicy:
                returnMessage = "Biometric verification is disabled by policy.";
                break;
            case Windows.Security.Credentials.UI.UserConsentVerificationResult.NotConfiguredForUser:
                returnMessage = "The user has no fingerprints registered. Please add a fingerprint to the " +
                                "fingerprint database and try again.";
                break;
            case Windows.Security.Credentials.UI.UserConsentVerificationResult.RetriesExhausted:
                returnMessage = "There have been too many failed attempts. Fingerprint authentication canceled.";
                break;
            case Windows.Security.Credentials.UI.UserConsentVerificationResult.Canceled:
                returnMessage = "Fingerprint authentication canceled.";
                break;
            default:
                returnMessage = "Fingerprint authentication is currently unavailable.";
                break;
        }
    }
    catch (Exception ex)
    {
        returnMessage = "Fingerprint authentication failed: " + ex.ToString();
    }

    return returnMessage;
}

Universal Windows Platform (UWP) apps using C#

This code example is for a Universal Windows Platform (UWP) app. It shows a request for fingerprint verification followed by returning a message that describes the result. The code calls the UserConsentVerifier.RequestVerificationAsync method, which is appropriate for UWP apps.

private async System.Threading.Tasks.Task<string> RequestConsent(string userMessage)
{
    string returnMessage;

    if (String.IsNullOrEmpty(userMessage))
    {
        userMessage = "Please provide fingerprint verification.";
    }

    try
    {
        // Request the logged on user's consent via fingerprint swipe.
        var consentResult = await Windows.Security.Credentials.UI.UserConsentVerifier.RequestVerificationAsync(userMessage);

        switch (consentResult)
        {
            case Windows.Security.Credentials.UI.UserConsentVerificationResult.Verified:
                returnMessage = "Fingerprint verified.";
                break;
            case Windows.Security.Credentials.UI.UserConsentVerificationResult.DeviceBusy:
                returnMessage = "Biometric device is busy.";
                break;
            case Windows.Security.Credentials.UI.UserConsentVerificationResult.DeviceNotPresent:
                returnMessage = "No biometric device found.";
                break;
            case Windows.Security.Credentials.UI.UserConsentVerificationResult.DisabledByPolicy:
                returnMessage = "Biometric verification is disabled by policy.";
                break;
            case Windows.Security.Credentials.UI.UserConsentVerificationResult.NotConfiguredForUser:
                returnMessage = "The user has no fingerprints registered. Please add a fingerprint to the " +
                                "fingerprint database and try again.";
                break;
            case Windows.Security.Credentials.UI.UserConsentVerificationResult.RetriesExhausted:
                returnMessage = "There have been too many failed attempts. Fingerprint authentication canceled.";
                break;
            case Windows.Security.Credentials.UI.UserConsentVerificationResult.Canceled:
                returnMessage = "Fingerprint authentication canceled.";
                break;
            default:
                returnMessage = "Fingerprint authentication is currently unavailable.";
                break;
        }
    }
    catch (Exception ex)
    {
        returnMessage = "Fingerprint authentication failed: " + ex.ToString();
    }

    return returnMessage;
}

Remarks

You can use UserConsentVerifier to enhance the security of your app by including a request for verification whenever the user is required to consent to a particular action. For example, you can require fingerprint authentication before authorizing an in-app purchase or access to restricted resources. You can use UserConsentVerifier to determine whether fingerprint authentication is supported for the current computer by using the CheckAvailabilityAsync method, and then request user consent from a fingerprint scan by using the RequestVerificationAsync method.

Methods

CheckAvailabilityAsync()	Checks to see whether a verifier device, such as a Microsoft Passport PIN, Windows Hello, or fingerprint reader, is available.
RequestVerificationAsync(String)	Performs a verification using a device such as Microsoft Passport PIN, Windows Hello, or a fingerprint reader. This API is for Universal Windows Platform (UWP) apps. The alternative API to use for a desktop app is described in Examples in UserConsentVerifier class.

Applies to