How to: Read Typed Data Using a Schema Mapping
The following example uses the XmlReader to return a typed object. Because of the format of the hire-date element, it cannot be successfully converted to a DateTime object. However, if you use a schema to map the element to the xs:date type you can do the necessary type conversion.
Example
The following example uses the ReadElementContentAsDateTime method to return the hire-date element as a DateTime object.
' Create a validating XmlReader object. The schema
' provides the necessary type information.
Dim settings As XmlReaderSettings = New XmlReaderSettings()
settings.ValidationType = ValidationType.Schema
settings.Schemas.Add("urn:empl-hire", "hireDate.xsd")
Using reader As XmlReader = XmlReader.Create("hireDate.xml", settings)
' Move to the hire-date element.
reader.MoveToContent()
reader.ReadToDescendant("hire-date")
' Return the hire-date as a DateTime object.
Dim hireDate As DateTime = reader.ReadElementContentAsDateTime()
Console.WriteLine("Six Month Review Date: {0}", hireDate.AddMonths(6))
End Using
// Create a validating XmlReader object. The schema
// provides the necessary type information.
XmlReaderSettings settings = new XmlReaderSettings();
settings.ValidationType = ValidationType.Schema;
settings.Schemas.Add("urn:empl-hire", "hireDate.xsd");
using (XmlReader reader = XmlReader.Create("hireDate.xml", settings)) {
// Move to the hire-date element.
reader.MoveToContent();
reader.ReadToDescendant("hire-date");
// Return the hire-date as a DateTime object.
DateTime hireDate = reader.ReadElementContentAsDateTime();
Console.WriteLine("Six Month Review Date: {0}", hireDate.AddMonths(6));
}
Input
The example uses the hireDate.xml and hireDate.xsd files as input.
hireDate.xml
<employee xmlns="urn:empl-hire">
<ID>12365</ID>
<hire-date>2003-01-08</hire-date>
<title>Accountant</title>
</employee>
hireDate.xsd
<?xml version="1.0"?>
<xs:schema attributeFormDefault="unqualified" elementFormDefault="qualified" targetNamespace="urn:empl-hire" xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="employee">
<xs:complexType>
<xs:sequence>
<xs:element name="ID" type="xs:unsignedShort" />
<xs:element name="hire-date" type="xs:date" />
<xs:element name="title" type="xs:string" />
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:schema>
Output
Six Month Review Date: 7/8/2003 12:00:00 AM