如何实现Windows.Forms/Xamarin.Forms从外部URI/链接打开应用并传参？

Hey there! Let's walk through how to handle deep linking (opening your app via external URIs) for both Windows Forms and Xamarin.Forms, plus a cross-platform approach that works like Android's Intent system.

To make your Windows Forms app respond to external URIs, you need two key steps: register a custom URI scheme, then handle incoming URIs in your app.

Step 1: Register the URI Scheme #

Windows needs to know which app handles your custom URI. For development, you can set this up via the Registry:

• Open Registry Editor (regedit.exe)
• Navigate to HKEY_CLASSES_ROOT
• Create a new key named after your scheme (e.g., mywinapp)
• Set the default value to a friendly name like "My Windows Forms App"
• Add a string value named URL Protocol with an empty value
• Create subkeys shell > open > command
• Set the default value of command to your app's EXE path, followed by "%1" (to pass the URI as a command-line argument)

Step 2: Handle Incoming URIs in Your App #

When your app is launched via the URI, the full URI will be passed as a command-line argument. Catch this in your Program.cs:

static void Main(string[] args)
{
    Application.EnableVisualStyles();
    Application.SetCompatibleTextRenderingDefault(false);

    string incomingData = null;
    if (args.Length > 0)
    {
        // Parse the incoming URI (e.g., mywinapp://open?data=hello-world)
        var uri = new Uri(args[0]);
        var queryParams = System.Web.HttpUtility.ParseQueryString(uri.Query);
        incomingData = queryParams["data"];
    }

    // Pass the data to your main form
    Application.Run(new MainForm(incomingData));
}

Then update your MainForm constructor to accept and use the incoming data:

public MainForm(string incomingData = null)
{
    InitializeComponent();
    if (!string.IsNullOrEmpty(incomingData))
    {
        MessageBox.Show($"Received data: {incomingData}");
        // Add your logic to process the data here
    }
}

Xamarin.Forms requires platform-specific configuration, but we can use Xamarin.Essentials to handle most of the cross-platform heavy lifting.

Step 1: Platform Configuration #

Android

Open AndroidManifest.xml and add an intent filter inside your <activity> tag to register your URI scheme:

<intent-filter>
    <action android:name="android.intent.action.VIEW" />
    <category android:name="android.intent.category.DEFAULT" />
    <category android:name="android.intent.category.BROWSABLE" />
    <!-- Replace "myxamarinapp" with your custom scheme -->
    <data android:scheme="myxamarinapp" />
</intent-filter>

iOS

Open Info.plist and add URL scheme configuration:

<key>CFBundleURLTypes</key>
<array>
    <dict>
        <key>CFBundleURLSchemes</key>
        <array>
            <!-- Replace "myxamarinapp" with your custom scheme -->
            <string>myxamarinapp</string>
        </array>
    </dict>
</array>

Then update AppDelegate.cs to pass incoming URIs to Xamarin.Essentials:

public override bool OpenUrl(UIApplication app, NSUrl url, NSDictionary options)
{
    if (Xamarin.Essentials.AppLinks.OpenUrl(url))
        return true;
    return base.OpenUrl(app, url, options);
}

Step 2: Handle Incoming Links in Xamarin.Forms #

In your shared App.xaml.cs, subscribe to the AppLinkReceived event to process incoming URIs:

protected override void OnStart()
{
    Xamarin.Essentials.AppLinks.OnAppLinkReceived += AppLinks_OnAppLinkReceived;
}

private void AppLinks_OnAppLinkReceived(object sender, Xamarin.Essentials.AppLinkReceivedEventArgs e)
{
    var uri = e.Uri;
    var queryParams = System.Web.HttpUtility.ParseQueryString(uri.Query);
    var incomingData = queryParams["data"];

    // Navigate to a page and pass the data
    MainPage.Navigation.PushAsync(new DataDisplayPage(incomingData));
}

Step 3: Share Links with Data #

To share a link that opens your app and passes data, use Xamarin.Essentials' Share API:

private async Task ShareAppLink()
{
    // Encode the data to avoid URI issues
    var encodedData = Uri.EscapeDataString("Check out this shared content!");
    var appLink = new Uri($"myxamarinapp://share?data={encodedData}");

    await Xamarin.Essentials.Share.RequestAsync(new Xamarin.Essentials.ShareTextRequest
    {
        Text = "Open this in my Xamarin app!",
        Uri = appLink.ToString()
    });
}

If you want a unified approach similar to Android's Intent system, you can wrap the platform-specific logic in an abstract service:

Step 1: Define a Cross-Platform Interface #

public interface IDeepLinkService
{
    // Register the URI scheme (if needed for the platform)
    void RegisterScheme(string scheme);
    // Open another app via URI (or your own app)
    Task<bool> OpenUri(string uri);
    // Get the incoming URI when the app is launched via deep link
    string GetIncomingUri();
}

Step 2: Implement the Service for Each Platform #

• Windows Forms: Implement using command-line arguments and Registry registration
• Android: Use Intent.ACTION_VIEW to open URIs, and extract data from incoming intents
• iOS: Use UIApplication.SharedApplication.OpenUrl and extract data from incoming URLs

Xamarin.Essentials already provides most of this functionality out of the box, so using it is usually the fastest path instead of building a custom service.

内容的提问来源于stack exchange，提问作者Javi