VB.Net by API/System.Data/DataSet — различия между версиями

Материал из VB Эксперт
Перейти к: навигация, поиск
м (1 версия)
 
(нет различий)

Текущая версия на 12:49, 26 мая 2010

DataSet.GetXml()

  
 
Imports System.Data.SqlClient
Imports System.Data
Module Module1
    Sub Main()
        Try
            Dim DS As New DataSet()
            DS.ReadXml("Authors.XML")
            Dim XMLContent As String = DS.GetXml()
            Dim I As Integer
            For I = 0 To DS.Tables(0).Rows.Count - 1
                DS.Tables(0).Rows(I).Item("Author") = UCase(DS.Tables(0).Rows(I).Item("Author"))
            Next
            For I = 0 To DS.Tables(0).Rows.Count - 1
                Console.WriteLine(DS.Tables(0).Rows(I).Item("Title"))
                Console.WriteLine(DS.Tables(0).Rows(I).Item("Author"))
                Console.WriteLine(DS.Tables(0).Rows(I).Item("Publisher"))
                Console.WriteLine(DS.Tables(0).Rows(I).Item("Price"))
            Next
            DS.WriteXml("NewAuthors.xml")
        Catch Ex As Exception
            Console.WriteLine("Exception: " & Ex.Message)
            Console.WriteLine(Ex.ToString)
            Console.ReadLine()
        End Try
    End Sub
End Module


DataSet.ReadXml

  

Imports System.Data.SqlClient
Imports System.Data
Module Module1
    Sub Main()
        Try
            Dim DS As New DataSet()
            DS.ReadXml("Authors.XML")
            Dim XMLContent As String = DS.GetXml()
            Dim I As Integer
            For I = 0 To DS.Tables(0).Rows.Count - 1
                Console.WriteLine(DS.Tables(0).Rows(I).Item("Title"))
                Console.WriteLine(DS.Tables(0).Rows(I).Item("Author"))
                Console.WriteLine(DS.Tables(0).Rows(I).Item("Publisher"))
                Console.WriteLine(DS.Tables(0).Rows(I).Item("Price"))
            Next
        Catch Ex As Exception
            Console.WriteLine("Exception: " & Ex.Message)
            Console.WriteLine(Ex.ToString)
        End Try
    End Sub
End Module


DataSet.ReadXmlSchema

  

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>


DataSet.Tables

  
Imports System
Imports System.Xml
Imports System.Xml.Schema
Imports System.IO
Imports System.Data.SqlClient
Imports System.Collections
Imports System.Data

Public Class MainClass
    
    Shared Sub Main()
        Dim da As New SqlDataAdapter( _
                   "SELECT ID, FirstName, LastName FROM Employee", _
                   "Server=(local)\SQLEXPRESS;Initial Catalog=MyDatabase;Integrated Security=SSPI")
        Dim ds As New DataSet("Employee")
        da.FillSchema(ds, SchemaType.Source)
        ds.ReadXml("Employee.xml")
        Dim Table As DataTable = ds.Tables(0)
        Dim numCols As Integer = Table.Columns.Count
        Dim Row As DataRow
        For Each Row In Table.Rows
            Dim i As Integer
            For i = 0 To numCols - 1
                Console.WriteLine(Table.Columns(i).ColumnName & " = " & Row(i))
            Next
            Console.WriteLine()
        Next
    End Sub
End Class


DataSet.WriteXmlSchema

  
Imports System
Imports System.Xml
Imports System.Xml.Schema
Imports System.IO
Imports System.Collections
Imports System.Data
Public Class MainClass
    
    Shared Sub Main()
      Dim nsArray As String() = {""}
      Dim MyDS As DataSet = New DataSet()
      MyDS.ReadXml("book.xml")
      MyDS.WriteXmlSchema("InferredSchema.xds")
    End Sub
End Class