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DataSet.ReadXmlSchema Method (XmlReader)

Reads the XML schema from the specified XmlReader into the DataSet.

Namespace:  System.Data
Assembly:  System.Data (in System.Data.dll)

'Declaration
Public Sub ReadXmlSchema ( _
	reader As XmlReader _
)

Parameters

reader
Type: System.Xml.XmlReader

The XmlReader from which to read.

Use the ReadXmlSchema method to create the schema for a DataSet. The schema includes table, relation, and constraint definitions.

The XML schema is written using the XSD standard.

NoteNote

Data corruption can occur if the msdata:DataType and the xs:type types do not match. No exception will be thrown.

The ReadXmlSchema method is generally invoked before invoking the ReadXml method which is used to fill the DataSet.

The System.Xml.XmlReader class is abstract. A class that inherits from the XmlReader is the System.Xml.XmlTextReader class.

NoteNote

If the schema for your DataSet contains elements of the same name, but different type, in the same namespace, an exception is be thrown when you attempt to read the schema into the DataSet with ReadXmlSchema. This exception does not occur if you are using .NET Framework version 1.0.

The following example creates a new DataSet and System.IO.FileStream object. The FileStream object, created with a file path and file name, is used to create an System.Xml.XmlTextReader that is passed as an argument to the ReadXmlSchema method.

Private Sub ReadSchemaFromXmlTextReader()
    ' Create the DataSet to read the schema into. 
    Dim thisDataSet As New DataSet()

    ' Set the file path and name. Modify this for your purposes. 
    Dim filename As String = "Schema.xml" 

    ' Create a FileStream object with the file path and name. 
    Dim stream As New System.IO.FileStream _
       (filename, System.IO.FileMode.Open)

    ' Create a new XmlTextReader object with the FileStream. 
    Dim xmlReader As New System.Xml.XmlTextReader(stream)

    ' Read the schema into the DataSet and close the reader.
    thisDataSet.ReadXmlSchema(xmlReader)
    xmlReader.Close()
End Sub

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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