VB.NET DataSet.ReadXmlSchema方法代码示例

Private Sub ReadSchemaFromFileStream(thisDataSet As DataSet)
    ' Set the file path and name. Modify this for your purposes.
    Dim filename As String = "Schema.xml"

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

    ' Read the schema into the DataSet.
    thisDataSet.ReadXmlSchema(stream)

    ' Close the FileStream.
    stream.Close()
End Sub

Private Sub ReadSchemaFromStreamReader()
    ' 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 StreamReader object with the file path and name.
    Dim readStream As New System.IO.StreamReader(filename)

    ' Invoke the ReadXmlSchema method with the StreamReader object.
    thisDataSet.ReadXmlSchema(readStream)

    ' Close the StreamReader
    readStream.Close()
End Sub

Private Sub ReadSchemaFromFile()
    ' 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"

    ' Invoke the ReadXmlSchema method with the file name.
    thisDataSet.ReadXmlSchema(filename)
End Sub

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

' 导入命名空间
Imports System
Imports System.Xml
Imports System.Xml.Schema
Imports System.IO
Imports System.Data


Public Class MainClass
    
    Shared Sub Main()
        Dim MyDS As New DataSet()
        MyDS.ReadXmlSchema("book.xdr")
        Console.WriteLine("Schema Loaded.")

        Dim Table As DataTable
        For Each Table In MyDS.Tables
            Console.WriteLine("Table {0}, {1} Columns", _
                              Table.TableName, Table.Columns.Count)
        Next

        MyDS.ReadXml("book.xml", XmlReadMode.IgnoreSchema)
        Console.WriteLine("Data Loaded.")
        Console.WriteLine()
        Dim Book As DataRow
        For Each Book In MyDS.Tables("Book").Rows
            Console.WriteLine("{0} : {1} - ${2}", Book("Title"))
        Next
    End Sub

End Class


'book.xdr
'<?xml version = "1.0"?>

'<Schema xmlns = "urn:schemas-microsoft-com:xml-data">
'   <ElementType name = "title" content = "textOnly" 
'      model = "closed" />

'   <ElementType name = "book" content = "eltOnly" model = "closed">
'      <element type = "title" minOccurs = "1" maxOccurs = "1" />
'   </ElementType>

'   <ElementType name = "books" content = "eltOnly" model = "closed">
'      <element type = "book" minOccurs = "0" maxOccurs = "*" />
'   </ElementType>
'</Schema>

'File: book.xml
'<?xml version = "1.0"?>

'<books xmlns = "x-schema:book.xdr">
'   <book>
'      <title>C# How to Program</title>
'   </book>

'   <book>
'      <title>Java How to Program, 4/e</title>
'   </book>

'   <book>
'      <title>Visual Basic .NET How to Program</title>
'   </book>

'   <book>
'      <title>Advanced Java 2 Platform How to Program</title>
'   </book>

'   <book>
'      <title>Python How to Program</title>
'   </book>
'</books>