Applied XML Programming for Microsoft .NET.pdf - Csbdu.in

In particular, the XmlConvert class will not recognize the first string as a correct date.As for the salary, you'll get a message stating that the input string is not in the correctformat.If you had created the XML code programmatically using an XML writer (more on XMLwriters in Chapter 4) and .NET strong types, the XML fragment you're working withwould be slightly different, as shown here:2001-02-08150000To be understood in XML, a date must be in YYYY-MM-DD format and a double valueshould not include any locale-dependent element such as the digit group symbol. If thedouble value includes a fractional part, use a decimal point to separate it from theinteger part. Likewise, XmlConvert recognizes Booleans only if they are expressed astrue/false or 1/0 pairs.NoteAnother aspect that makes the difference between the System.Convert and XmlConvert classes even sharper is the fact thatXmlConvert does not support custom format providers. TheXmlConvert class works as a translator to and from .NET types andXSD types. When the conversion takes place, the result isrigorously locale independent.Round-Tripping Non-XML StringsNot all characters available on a given platform are necessarily valid XML characters.Only the characters included in the range of allowed characters defined in the XMLspecification (www.w3.org/TR/2000/REC-xml-20001006.html) can be safely used forelement and attribute names.The XmlConvert class provides key functions for tunneling non-XML names throughXML over a round-trip to some servers. When names contain characters that are invalidin XML names, the methods EncodeName and DecodeName can adjust them to fit intoan XML name schema. For example, several applications, including Microsoft SQLServer and Microsoft Office, allow and support Unicode characters in their documents.However, some of these characters are not valid in XML names. The typicalcircumstance that demonstrates the importance of XmlConvert occurs when youmanipulate, say, a database column name containing blanks. Although SQL Serverallows a column name such as Invoice Details, that would not be a valid name for anXML stream. The word space must be replaced with its hexadecimal encoding. A validXML representation for the column name Invoice Details is the following string:Invoice_0x0020_DetailsYou can obtain that string by using EncodeName, as shown here:string xmlColName = XmlConvert.EncodeName("Invoice Details");The reverse operation is accomplished by using DecodeName. This method translatesan XML name back to its original form by unescaping any escaped sequence, asshown in the following code. Note that only fully escaped forms are detected. Forexample, only _0x0020_ is rendered as a blank space.31