.net – Dual-deploying a WPF app natively and as a XBAP

deploymentnetwpfxbap

How to create a WPF application that can be deployed as either a XBAP or as a native Windows application with as little overhead as possible? XBAPs are binary compatible with WPF Windows applications and run on top of the same CLR (Unlike Silverlight). They still differ in some ways.

From deployment point of view their largest difference is that a XBAP has a Page control as the main container while a Windows application has a Window control. It would be rather trivial to make the Windows application use the Page control but I feel (Feel free to disagree) that using a Page navigation method in a Windows application is rather unintuitive.

The second major difference is that XBAPs by default are executed in a partially trusted environment. This can be bypassed though and the XBAPs can be made run in full trust mode. The partial trust mode with XBAPs means you cannot access for example remote web services or native code from the XBAPs directly.

What would be an easy and maintainable way to achieve the following with the above issues?

Requirements

Deployable in both ways: as a XBAP over http and as a stand-alone WPF executable.
Shows information from a remote web server such as flickr or through an unmanaged API.
If possible, the deployment methods should remain faithful to their platforms. That is to say: Use Pages in XBAP where those make sense and dialogs in the Windows app where those make sense.

Restrictions

Platform optimised. The stuff required by the XBAP shouldn't affect the Windows client and vice versa.
The deployment options share as much code as possible. This helps in testing and maintenance.
Running the XBAP should be as simple as possible. Certificate prerequirement would defeat the purpose of a XBAP.

What I have gathered is that first requirement requires two separate projects. The second restriction could be worked upon by having a user control project which contains all the UI and is referenced by the two deployment projects. A WCF web service could work around the limitations of XBAPs.

If employing a solution similar to the above lines the first restriction would require some work as the Windows client could do without the WCF service as it's already running in full trust mode. Also the third requirement would need some deployment specific code so all the UI code cannot be in the user control project.

I'd like to know what solutions could be used to resolve these problems. Feel free to ignore the partial solution. It's there mainly to explain the point and to prevent the "Thought of this already" comments. So just to clarify, I'm interested in all solutions to this problem, not just those that abide to the partial solution.

The reason for interest to this is that a solution would mean there's no need to ponder between a WPF Windows app and a XBAP as these both could be created with little more effort and the client could choose whichever suits them best.

Best Answer

You may want to take a look at Prism (at codeplex) It helps to target Wpf, Xbap and Silverlight with minimum code changes (the amount of extra work depends on your project).

Here's how to use it to create Wpf and Xbap application: Prism and XBap Applications

Related Solutions

C# – How to make a textbox that only accepts numbers

Two options:

Use a NumericUpDown instead. NumericUpDown does the filtering for you, which is nice. Of course it also gives your users the ability to hit the up and down arrows on the keyboard to increment and decrement the current value.

Handle the appropriate keyboard events to prevent anything but numeric input. I've had success with this two event handlers on a standard TextBox:

private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
    if (!char.IsControl(e.KeyChar) && !char.IsDigit(e.KeyChar) &&
        (e.KeyChar != '.'))
    {
            e.Handled = true;
    }

    // only allow one decimal point
    if ((e.KeyChar == '.') && ((sender as TextBox).Text.IndexOf('.') > -1))
    {
        e.Handled = true;
    }
}

You can remove the check for '.' (and the subsequent check for more than one '.') if your TextBox shouldn't allow decimal places. You could also add a check for '-' if your TextBox should allow negative values.

If you want to limit the user for number of digit, use: textBox1.MaxLength = 2; // this will allow the user to enter only 2 digits

C# – How to get a TextBox to only accept numeric input in WPF

Add a preview text input event. Like so: <TextBox PreviewTextInput="PreviewTextInput" />.

Then inside that set the e.Handled if the text isn't allowed. e.Handled = !IsTextAllowed(e.Text);

I use a simple regex in IsTextAllowed method to see if I should allow what they've typed. In my case I only want to allow numbers, dots and dashes.

private static readonly Regex _regex = new Regex("[^0-9.-]+"); //regex that matches disallowed text
private static bool IsTextAllowed(string text)
{
    return !_regex.IsMatch(text);
}

If you want to prevent pasting of incorrect data hook up the DataObject.Pasting event DataObject.Pasting="TextBoxPasting" as shown here (code excerpted):

// Use the DataObject.Pasting Handler 
private void TextBoxPasting(object sender, DataObjectPastingEventArgs e)
{
    if (e.DataObject.GetDataPresent(typeof(String)))
    {
        String text = (String)e.DataObject.GetData(typeof(String));
        if (!IsTextAllowed(text))
        {
            e.CancelCommand();
        }
    }
    else
    {
        e.CancelCommand();
    }
}

Best Answer

Related Solutions

C# – How to make a textbox that only accepts numbers

C# – How to get a TextBox to only accept numeric input in WPF

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