Beginning Web Development, Silverlight, and ASP.NET AJAX

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CHAPTER 7 ■ .NET 3.0: WINDOWS COMMUNICATION FOUNDATION
}
catch
{
return String.Empty;
}
finally
{
if (xmlWriter != null)
xmlWriter.Close();
}
}
The DataTable has the facility to write XML to an XMLWriter. This XMLWriter can
then write to a memory stream that can be read out as a string. Thus, the XML is loaded
into a string that can be returned. And as the string is a simple data type, it can be passed
across the wire without a DataContract.
Now, to control how this service behaves, you’ll use the Web.config file. Here’s a
sample Web.config file that will work with this service. You’ll build on this later to provide
attributes such as security to your service.