в 16:40, 26 мая 2010

2010-05-26T16:40:06Z

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2010-05-26T12:45:35Z

1 версия

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==Add 5 new green Fords to the incoming document==

<source lang="vbnet">
Module Program
Sub Main()
Dim doc As XElement = XElement.Load("Inventory.xml")
For i As Integer = 0 To 4
Dim newCar As New XElement("Car", _
New XAttribute("ID", i + 1000), _
New XElement("Color", "Green"), _
New XElement("Make", "Ford"), _
New XElement("PetName", ""))
doc.Add(newCar)
Next
Console.WriteLine(doc)
End Sub
End Module

</source>

==Adding XElement to XElement==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim xml As XElement = XElement.Load("People.xml")
xml.AddFirst(New XElement("person", _
New XElement("id", 5), _
New XElement("firstname", "Tom"), _
New XElement("lastname", "Cruise"), _
New XElement("idrole", 1)))
Console.WriteLine(xml)
End Sub
End Module

</source>

==Add the new node to the bottom of the XML tree==

<source lang="vbnet">
Imports System
Imports System.Xml.Linq
Public Class MainClass
Public Shared Sub Main()
Dim employees As XElement = XElement.Load("Employees.xml")
Dim newEmployee = <Employee id=<%= 1 %>>
<Name>First</Name>
<Title>Coder</Title>
<HireDate>07/15/2006</HireDate>
<HourlyRate>9.95</HourlyRate>
</Employee>
employees.Add(newEmployee)
For Each ele In employees.<Employee>
ele.Add(<TerminationDate></TerminationDate>)
ele.Add(New XAttribute("Status", ""))
Next
Console.WriteLine(employees.ToString())
End Sub
End Class

</source>

==After elements==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim xml As XElement = XElement.Load("People.xml")
Dim firstName As XElement = xml.Descendants("firstname").First()

Console.WriteLine("After <firstname>")
For Each tag In firstName.ElementsAfterSelf()
Console.WriteLine(tag.Name)
Next
End Sub
End Module

</source>

==Before elements==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim xml As XElement = XElement.Load("People.xml")
Dim firstName As XElement = xml.Descendants("firstname").First()
Console.WriteLine("Before <firstname>")
For Each tag In firstName.ElementsBeforeSelf()
Console.WriteLine(tag.Name)
Next
End Sub
End Module

</source>

==Build an XElement from string==

<source lang="vbnet">
Class Car
Public PetName As String
Public ID As Integer
End Class
Module Program
Sub Main()
Dim myElement As String = _
"<Car ID="3">" & _
"<Color>Yellow</Color>" & _
"<Make>Yugo</Make>" & _
"</Car>"
Dim newElement As XElement = XElement.Parse(myElement)
Console.WriteLine(newElement)
Console.WriteLine()
" Load the SimpleInventory.xml file.
Dim myDoc As XDocument = XDocument.Load("SimpleInventory.xml")
Console.WriteLine(myDoc)
End Sub
End Module

</source>

==Convert comma separated value to Xml==

<source lang="vbnet">

Imports System
Imports System.Xml.Linq
Imports Microsoft.VisualBasic.FileIO
Imports System.Text
Imports System.IO
Public Class MainClass
Public Shared Sub Main(ByVal args As String())
Dim xmlTree As XElement
Using parser As TextFieldParser = My.ruputer.FileSystem.OpenTextFieldParser("data.txt")
parser.TextFieldType = FieldType.Delimited
parser.Delimiters = New String() {","}
parser.HasFieldsEnclosedInQuotes = True
xmlTree = <Employees></Employees>
Dim currentRow As String()
Do While Not parser.EndOfData
currentRow = parser.ReadFields
xmlTree.Add(<Employee id=<%= currentRow(0) %>>
<Name><%= currentRow(1) %></Name>
<Title><%= currentRow(2) %></Title>
<HireDate><%= currentRow(3) %></HireDate>
<HourlyRate><%= currentRow(4) %></HourlyRate>
</Employee>)
Loop
End Using
Console.WriteLine(xmlTree)
End Sub
End Class

</source>

==Create an in-memory XML document==

<source lang="vbnet">
Class Car
Public PetName As String
Public ID As Integer
End Class
Module Program
Sub Main()
".
Dim inventoryDoc As XDocument = _
New XDocument( _
New XDeclaration("1.0", "utf-8", "yes"), _
New XComment("Current Inventory of AutoLot"), _
New XElement("Inventory", _
New XElement("Car", New XAttribute("ID", "1"), _
New XElement("Color", "Green"), _
New XElement("Make", "BMW"), _
New XElement("PetName", "Stan") _
), _
New XElement("Car", New XAttribute("ID", "2"), _
New XElement("Color", "Pink"), _
New XElement("Make", "Yugo"), _
New XElement("PetName", "A") _
) _
) _
)
Console.WriteLine(inventoryDoc)
inventoryDoc.Save("SimpleInventory.xml")
End Sub

End Module

</source>

==Create a query to convert the xml data into fields delimited by quotes and commas.==

<source lang="vbnet">

Imports System
Imports System.Xml.Linq
Imports Microsoft.VisualBasic.FileIO
Imports System.Text
Imports System.IO
Public Class MainClass
Public Shared Sub Main(ByVal args As String())
Dim employees As XElement = XElement.Load("xmlFile.xml")
Dim delimitedData As New StringBuilder
Dim xmlData = _
From emp In employees.<Employee> _
Select _
String.Format("""{0}"",""{1}"",""{2}"",""{3}"",""{4}""", _
emp.@id, emp.<Name>.Value, _
emp.<Title>.Value, emp.<HireDate>.Value, _
emp.<HourlyRate>.Value)
End Sub
End Class

</source>

==Create a single XML element==

<source lang="vbnet">

Class Car
Public PetName As String
Public ID As Integer
End Class
Module Program
Sub Main()
Dim inventory As XElement = _
<Inventory>
<Car ID="1">
<Color>Green</Color>
<Make>BMW</Make>
<PetName>Stan</PetName>
</Car>
</Inventory>
" Call ToString() on our XElement.
Console.WriteLine(inventory)
End Sub

End Module

</source>

==Enumerate over the array to build an XElement==

<source lang="vbnet">
Imports System.Collections.Generic

Class Car
Public PetName As String
Public ID As Integer
End Class
Module Program
Sub Main()
Dim data As New List(Of Car)
data.Add(New Car With {.PetName = "A", .ID = 10})
data.Add(New Car With {.PetName = "Pat", .ID = 11})
data.Add(New Car With {.PetName = "Danny", .ID = 12})
data.Add(New Car With {.PetName = "B", .ID = 13})

Dim vehicles As XElement = _
New XElement("Inventory", _
From c In data _
Select New XElement("Car", _
New XAttribute("ID", c.ID), _
New XElement("PetName", c.PetName) _
) _
)
Console.WriteLine(vehicles)
End Sub
End Module

</source>

==First Last Example==

<source lang="vbnet">

Imports System.Reflection
Imports System

Public Class Role
Public ID As Integer
Public RoleDescription As String
End Class
Public Class Person
Public ID As Integer
Public IDRole As Integer
Public LastName As String
Public FirstName As String
End Class
Public Class Salary
Public IDPerson As Integer
Public Year As Integer
Public SalaryYear As Double
End Class
Module Module1
Sub Main()
Dim people As New List(Of Person)(New Person() { _
New Person With {.ID = 1, .IDRole = 1, .LastName = "A", .FirstName = "Brad"}, _
New Person With {.ID = 2, .IDRole = 2, .LastName = "G", .FirstName = "Tom"} _
})
Dim roles As New List(Of Role)(New Role() { _
New Role With {.ID = 1, .RoleDescription = "Manager"}, _
New Role With {.ID = 2, .RoleDescription = "Developer"} _
})

Dim salaries As New List(Of Salary)(New Salary() { _
New Salary With {.IDPerson = 1, .Year = 2004, .SalaryYear = 10000.0}, _
New Salary With {.IDPerson = 1, .Year = 2005, .SalaryYear = 15000.0}, _
New Salary With {.IDPerson = 2, .Year = 2005, .SalaryYear = 15000.0} _
})
FirstLastExample()

End Sub
Function firstFunc(ByVal n As Integer) As Boolean
Return (n Mod 2 = 0)
End Function
Function lastFunc(ByVal n As Integer) As Boolean
Return (n Mod 2 = 0)
End Function

Public Sub FirstLastExample()
Dim numbers As Integer() = New Integer() {1, 2, 3, 4, 5, 6, 7, 8, 9}
Dim firstDelegate As New Func(Of Integer, Boolean)(AddressOf firstFunc)
Dim lastDelegate As New Func(Of Integer, Boolean)(AddressOf lastFunc)
Dim query = numbers.First()
Console.WriteLine("The first element in the sequence")
query = numbers.Last()
Console.WriteLine("The last element in the sequence")
Console.WriteLine("The first even element in the sequence")
query = numbers.First(firstDelegate)
Console.WriteLine("The last even element in the sequence")
query = numbers.Last(lastDelegate)
End Sub
End Module

</source>

==FirstLast Or Default Example==

<source lang="vbnet">
Imports System.Reflection
Imports System

Public Class Role
Public ID As Integer
Public RoleDescription As String
End Class
Public Class Person
Public ID As Integer
Public IDRole As Integer
Public LastName As String
Public FirstName As String
End Class
Public Class Salary
Public IDPerson As Integer
Public Year As Integer
Public SalaryYear As Double
End Class
Module Module1
Sub Main()
Dim people As New List(Of Person)(New Person() { _
New Person With {.ID = 1, .IDRole = 1, .LastName = "A", .FirstName = "Brad"}, _
New Person With {.ID = 2, .IDRole = 2, .LastName = "G", .FirstName = "Tom"} _
})
Dim roles As New List(Of Role)(New Role() { _
New Role With {.ID = 1, .RoleDescription = "Manager"}, _
New Role With {.ID = 2, .RoleDescription = "Developer"} _
})

Dim salaries As New List(Of Salary)(New Salary() { _
New Salary With {.IDPerson = 1, .Year = 2004, .SalaryYear = 10000.0}, _
New Salary With {.IDPerson = 1, .Year = 2005, .SalaryYear = 15000.0}, _
New Salary With {.IDPerson = 2, .Year = 2005, .SalaryYear = 15000.0} _
})
FirstLastOrDefaultExample()
End Sub
Function firstFunc(ByVal n As Integer) As Boolean
Return (n Mod 2 = 0)
End Function
Function lastFunc(ByVal n As Integer) As Boolean
Return (n Mod 2 = 1)
End Function

Public Sub FirstLastOrDefaultExample()
Dim numbers As Integer() = New Integer() {1, 3, 5, 7, 9}
Dim firstDelegate As New Func(Of Integer, Boolean)(AddressOf firstFunc)
Dim lastDelegate As New Func(Of Integer, Boolean)(AddressOf lastFunc)
Dim query = numbers.FirstOrDefault(firstDelegate)
Console.WriteLine("The first even element in the sequence")
Console.WriteLine("The last odd element in the sequence")
query = numbers.LastOrDefault(lastDelegate)
End Sub
End Module

</source>

==First name element has attributes==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim xml As XElement = XElement.Load("People.xml")
Dim firstName As XElement = xml.Descendants("firstname").First()
Console.WriteLine("FirstName tag has attributes: {0}", firstName.HasAttributes)
End Sub
End Module

</source>

==First name tag has child elements==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim xml As XElement = XElement.Load("People.xml")
Dim firstName As XElement = xml.Descendants("firstname").First()
Console.WriteLine("FirstName tag has child elements: {0}", firstName.HasElements)
End Sub
End Module

</source>

==FirstName tag"s parent has child elements==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim xml As XElement = XElement.Load("People.xml")
Dim firstName As XElement = xml.Descendants("firstname").First()
Console.WriteLine("FirstName tag"s parent has child elements: {0}", firstName.Parent.HasElements)
End Sub
End Module

</source>

==Get child elements by name directly==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim xml As XElement = XElement.Load("People.xml")
Dim query = From p In xml.Elements("person") _
Where p.Element("id").value = 1 _
Select p
For Each record In query
Console.WriteLine("Person: {0} {1}", _
record.Element("firstname"), _
record.Element("lastname"))
Next

End Sub
End Module

</source>

==Get first descendant==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim xml As XElement = XElement.Load("People.xml")
Dim firstName As XElement = xml.Descendants("firstname").First()
Console.WriteLine(firstName.Parent)
End Sub
End Module

</source>

==Get value of each color using indexer==

<source lang="vbnet">
Module Program
Sub Main()
Dim doc As XElement = XElement.Load("Inventory.xml")
Dim ids = From c In doc.<Car> Select c.@carID
For i As Integer = 0 To doc.Nodes.Count - 1
Console.WriteLine(doc.<Car>(i).<Color>.Value)
Next
End Sub
End Module

</source>

==Is FirstName tag empty?==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim xml As XElement = XElement.Load("People.xml")
Dim firstName As XElement = xml.Descendants("firstname").First()
Console.WriteLine("Is FirstName tag empty? {0}", IIf(firstName.IsEmpty, "Yes", "No"))
End Sub
End Module

</source>

==Is idperson tag empty?==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim xml As XElement = XElement.Load("People.xml")
Dim idPerson As XElement = xml.Descendants("idperson").First()
Console.WriteLine("Is idperson tag empty? {0}", IIf(idPerson.IsEmpty, "Yes", "No"))
End Sub
End Module

</source>

==Load the Employees.xml and store the contents into an XElement object.==

<source lang="vbnet">
Imports System
Imports System.Xml.Linq
Public Class MainClass
Public Shared Sub Main()
Dim employees As XElement = XElement.Load("Employees.xml")
End Sub
End Class

</source>

==Remove content from XElement==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim xml As XElement = XElement.Load("People.xml")
xml.Element("role").Remove()
Console.WriteLine(xml)
End Sub
End Module

</source>

==Remove from XElement==

<source lang="vbnet">
Imports System
Imports System.Data.DLinq
Imports System.Expressions
Imports System.Query
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim xml As XElement = XElement.Load("People.xml")
xml.Descendants("idperson").First().Remove()
xml.Elements("role").Remove()
Console.WriteLine(xml)
End Sub
End Module

</source>

==Remove the 4th Employee element.==

<source lang="vbnet">

Imports System
Imports System.Xml.Linq
Public Class MainClass
Public Shared Sub Main()
Dim employees As XElement = XElement.Load("Employees.xml")
employees.<Employee>.ElementAt(3).Remove()
End Sub
End Class

</source>

==Replace content from XElement==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim xml As XElement = XElement.Load("People.xml")
xml.Element("person").ReplaceNodes(New XElement("id", 5), _
New XElement("firstname", "A"), _
New XElement("lastname", "B"), _
New XElement("role", 1))
Console.WriteLine(xml)
End Sub
End Module

</source>

==Set new value to Xml document==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim xdoc As XDocument = XDocument.Load("data.xml")
xdoc.Element("PLAY").Element("PERSONA").SetValue("new value")
Console.WriteLine(xdoc.Element("PLAY").Element("PERSONA").Value)
End Sub
End Module

</source>

==The Root property returns the top-level XElement==

<source lang="vbnet">
Imports System
Imports System.Xml.Linq
Public Class MainClass
Public Shared Sub Main()
Dim xmlDoc As XDocument = XDocument.Load("Employees.xml")
Console.WriteLine("The document declaration is "{0}"", xmlDoc.Declaration.ToString)
Console.WriteLine("The root element is "{0}"", xmlDoc.Root.Name.LocalName)
End Sub
End Class

</source>

==Update attribute for XElement==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim xml As XElement = XElement.Load("People.xml")
Dim role As XElement = xml.Descendants("id").First()
Console.WriteLine(role)
role.SetAttributeValue("year", "2006")
Console.WriteLine(role)
End Sub
End Module

</source>

==Update XElement==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()

Dim xml As XElement = XElement.Load("People.xml")
Dim role As XElement = xml.Descendants("role").First()
Console.WriteLine(role)
role.SetElementValue("description", "Actor")
Console.WriteLine(role)
End Sub
End Module

</source>

==Using Ling query to create Xml output==

<source lang="vbnet">
Imports System
Imports System.Xml.Linq
Public Class Employee
Public EmployeeID As Integer
Public FirstName As String
Public LastName As String
Public Title As String
Public HireDate As DateTime
Public HourlyWage As Double
End Class

Public Class MainClass
Public Shared Sub Main()
Dim employeeList = New Employee() _
{New Employee With {.EmployeeID = 1, _
.FirstName = "A", _
.LastName = "M", _
.Title = "Tester", _
.HireDate = DateTime.Now, _
.HourlyWage = 10.0}, _
New Employee With {.EmployeeID = 2, _
.FirstName = "B", _
.LastName = "C", _
.Title = "Tester", _
.HireDate = DateTime.Now, _
.HourlyWage = 10.75}}
Dim employees = <Employees>
<%= From emp In employeeList _
Select _
<Employee id=<%= emp.EmployeeID %>>
<Name><%= emp.FirstName & " " & emp.LastName %></Name>
<Title><%= emp.Title %></Title>
<HireDate><%= emp.HireDate.ToString("MM/dd/yyyy") %></HireDate>
<HourlyRate><%= emp.HourlyWage %></HourlyRate>
</Employee> _
%>
</Employees>

employees.Save("Employees.xml")
Console.WriteLine(employees.ToString())
End Sub
End Class

</source>

==using XElement.Parse to load Xml from String==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim doc As String = "<people>" & _
"" & _
"<person>" & _
"<id>1</id>" & _
"<firstname>A</firstname>" & _
"<lastname>B</lastname>" & _
"<idrole>1</idrole>" & _
"</person>" & _
"</people>"
Dim xml As XElement = XElement.Parse(doc)
Console.WriteLine(xml)
End Sub
End Module

</source>

==Using Xml Linq to output Html==

<source lang="vbnet">
Imports System
Imports System.Reflection
Imports System.Xml
Module Module1
Sub Main()
Dim xml As XElement = XElement.Load("People.xml")
Dim html As New XElement("HTML", _
New XElement("BODY", _
New XElement("TABLE", _
New XElement("TH", "ID"), _
New XElement("TH", "Full Name"), _
New XElement("TH", "Role"), _
From p In xml.Descendants("person"), r In xml.Descendants("role") _
Where p.Element("idrole").Value = r.Element("id").Value _
Select New XElement("TR", _
New XElement("TD", p.Element("id").Value), _
New XElement("TD", p.Element("firstname").Value _
& " " & p.Element("lastname").Value), _
New XElement("TD", r.Element("roledescription").Value)))))
html.Save("People.html")
End Sub
End Module

</source>

==Xml literal with function return==

<source lang="vbnet">
Module Program
Sub Main()
Dim interiorColor As String = "White"
Dim exteriorColor As String = "Blue"
Dim car1 As XElement = _
<Automobile>
<petname><%= GetPetName() %></petname>
<color type="interior"><%= interiorColor %></color>
<color type="exterior"><%= exteriorColor %></color>
</Automobile>
Console.WriteLine(car1)
End Sub
Function GetPetName() As String
Return "Sidd"
End Function
End Module

</source>

==Xml Literal with string variable==

<source lang="vbnet">

Module Program
Sub Main()
Dim interiorColor As String = "White"
Dim exteriorColor As String = "Blue"
Dim car1 As XElement = _
<Automobile>
<petname><%= GetPetName() %></petname>
<color type="interior"><%= interiorColor %></color>
<color type="exterior"><%= exteriorColor %></color>
</Automobile>
Console.WriteLine(car1)
End Sub
Function GetPetName() As String
Return "Sidd"
End Function
End Module

</source>

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VB.Net/XML LINQ/XElement - История изменений

в 16:40, 26 мая 2010

Admin: 1 версия