Multidot extension for SaveFileDialog in C#?

Basically I'm trying to set the SaveFileDialog's filter like let's say to... "Xml Document (.asdf.xml)|.asdf.xml". It'll filter the files correctly when picking a file, but when actually saving the 开发者_JAVA百科file it only saves as a ".xml". Is this even supported?

I also can't think of a suitable workaround as most workarounds seem to involve needing to manually change the filename without the user knowing about it.

SupportMultiDottedExtensions = true;

Did you try this?

SaveFileDialog sfd = new SaveFileDialog();
sfd.Filter = "XML File (*.asdf.xml)|*.asdf.xml|All Files|";
sfd.SupportMultiDottedExtensions = true;

I took a stab at creating a quick win form using the SaveFileDialog and I was able to get a file to save with a multi-dot extension without issue. I'm using VS2010 and C#. Here's my code for a button click event handler:

private void button1_Click(object sender, EventArgs e)
{
    saveFileDialog1.Filter = "Xml Document (.asdf.xml)|*.asdf.xml";
    saveFileDialog1.ShowDialog();

    System.IO.FileStream fs = saveFileDialog1.OpenFile() as System.IO.FileStream;

    fs.Write(new byte[] { }, 0, 0);
    fs.Close();
}

It worked whether my filter used *.asdf.xml or .asdf.xml.

How is your code different? If it's the same, are you creating a new file or overwriting an existing one? I'm not sure what else would be different without seeing your code.

EDIT/UPDATE: Just saw sgrassie's answer about setting SupportMultiDottedExtension. I didn't set it, so maybe it defaults to true in C#/.NET 4.

HTH!