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Imports System.Data
Imports System.Data.OleDb
Imports System.IO
Imports System.Windows.Forms
public class DataTableToXML
public Shared Sub Main
Application.Run(New Form1)
End Sub
End class
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles MyBase.Load
Dim scores_dataset As New DataSet("Scores")
Dim students_table As DataTable = scores_dataset.Tables.Add("Students")
students_table.Columns.Add("FirstName", GetType(String))
students_table.Columns.Add("LastName", GetType(String))
students_table.Columns.Add("StudentId", GetType(Integer))
students_table.Columns("StudentId").Unique = True
Dim first_last_columns() As DataColumn = { _
students_table.Columns("FirstName"), _
students_table.Columns("LastName") _
}
students_table.Constraints.Add( _
New UniqueConstraint(first_last_columns))
' Make the TestScores table.
Dim test_scores_table As DataTable = _
scores_dataset.Tables.Add("TestScores")
' Add columns to the TestScores table.
test_scores_table.Columns.Add("StudentId", GetType(Integer))
test_scores_table.Columns.Add("TestNumber", GetType(Integer))
test_scores_table.Columns.Add("Score", GetType(Integer))
' Make the combined StudentId/TestNumber unique.
Dim studentid_testnumber_score_columns() As DataColumn = { _
test_scores_table.Columns("StudentId"), _
test_scores_table.Columns("TestNumber") _
}
test_scores_table.Constraints.Add( _
New UniqueConstraint(studentid_testnumber_score_columns))
' Make a relationship linking the
' two tables' StudentId fields.
scores_dataset.Relations.Add( _
"Student Test Scores", _
students_table.Columns("StudentId"), _
test_scores_table.Columns("StudentId"))
' Make some student data.
students_table.Rows.Add(New Object() {"A", "A", 1})
students_table.Rows.Add(New Object() {"B", "B", 2})
students_table.Rows.Add(New Object() {"C", "C", 3})
students_table.Rows.Add(New Object() {"D", "D", 4})
' Make some random test scores.
Dim score As New Random
For id As Integer = 1 To 4
For test_num As Integer = 1 To 10
test_scores_table.Rows.Add( _
New Object() {id, test_num, score.Next(65, 100)})
Next test_num
Next id
students_table.Columns("FirstName").ColumnMapping = MappingType.Element
students_table.Columns("LastName").ColumnMapping = MappingType.Element
students_table.Columns("StudentId").ColumnMapping = MappingType.Attribute
Dim string_writer As New StringWriter()
students_table.WriteXml(string_writer)
Console.WriteLine(string_writer)
grdScores.DataSource = scores_dataset
End Sub
End Class
<Global.Microsoft.VisualBasic.CompilerServices.DesignerGenerated()> _
Partial Public Class Form1
Inherits System.Windows.Forms.Form
'Form overrides dispose to clean up the component list.
<System.Diagnostics.DebuggerNonUserCode()> _
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing AndAlso components IsNot Nothing Then
components.Dispose()
End If
MyBase.Dispose(disposing)
End Sub
'Required by the Windows Form Designer
Private components As System.ComponentModel.IContainer
'NOTE: The following procedure is required by the Windows Form Designer
'It can be modified using the Windows Form Designer.
'Do not modify it using the code editor.
<System.Diagnostics.DebuggerStepThrough()> _
Private Sub InitializeComponent()
Me.grdScores = New System.Windows.Forms.DataGrid
CType(Me.grdScores, System.ComponentModel.ISupportInitialize).BeginInit()
Me.SuspendLayout()
'
'grdScores
'
Me.grdScores.DataMember = ""
Me.grdScores.Dock = System.Windows.Forms.DockStyle.Fill
Me.grdScores.HeaderForeColor = System.Drawing.SystemColors.ControlText
Me.grdScores.Location = New System.Drawing.Point(0, 0)
Me.grdScores.Name = "grdScores"
Me.grdScores.Size = New System.Drawing.Size(292, 273)
Me.grdScores.TabIndex = 1
'
'Form1
'
Me.AutoScaleDimensions = New System.Drawing.SizeF(6.0!, 13.0!)
Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font
Me.ClientSize = New System.Drawing.Size(292, 273)
Me.Controls.Add(Me.grdScores)
Me.Name = "Form1"
Me.Text = "MemoryDataSet"
CType(Me.grdScores, System.ComponentModel.ISupportInitialize).EndInit()
Me.ResumeLayout(False)
End Sub
Friend WithEvents grdScores As System.Windows.Forms.DataGrid
End Class
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