в 16:40, 26 мая 2010

2010-05-26T16:40:30Z

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2010-05-26T12:53:50Z

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==Array.Copy: Copy elements by position==

<source lang="vbnet">Public Class Tester
Public Shared Sub Main
Dim arrayA() As String = {"One", "Two", "Three", "Four", "Five", "Six"}
Console.WriteLine(Join(arrayA, ","))
Dim arrayB() As String = {"A", "B", "C", "D", "E", "E", "F", "G", "H"}
Console.WriteLine(Join(arrayB, ","))
" ----- Make a reference copy.
Dim arrayC() As String = arrayA
Console.WriteLine(Join(arrayC, ","))
" ----- Copy elements by position.
Array.Copy(arrayB, 0, arrayA, 1, 3)
Console.WriteLine(Join(arrayA, ","))
End Sub
End Class</source>
<pre class=codeResult>One,Two,Three,Four,Five,Six
A,B,C,D,E,E,F,G,H
One,Two,Three,Four,Five,Six
One,A,B,C,Five,Six</pre>

==Array.CreateInstance(GetType(Integer), 11)==

<source lang="vbnet">public class Test

public Shared Sub Main
Dim values As Array = _
Array.CreateInstance(GetType(Integer), 11)
For i As Integer = 0 To 10
values.SetValue(i, i)
Next i
End Sub

End class</source>

==Array.CreateInstance(GetType(String), 10)==

<source lang="vbnet">Option Strict On
Imports System.Collections.Generic
Public Module TypeNameFunction
Public Sub Main()
Console.WriteLine(TypeName(2 + 1.34)) " displays Double

Dim arr1 As Array = Array.CreateInstance(GetType(String), 10)
Console.WriteLine(TypeName(arr1))
Dim stringArray(10) As String
Console.Writeline(TypeName(stringArray))
Dim sl As New SortedList(Of String, String)
Console.WriteLine(TypeName(sl))
End Sub
End Module</source>
<pre class=codeResult>Double
String()
String()
SortedList(Of String,String)</pre>

==Array.GetLength, Array.GetUpperBound==

<source lang="vbnet">public class Test
public Shared Sub Main
Dim aryStatistics(14, 4) As Integer
Console.WriteLine("RANK: " & aryStatistics.Rank) "Dimensions in array.
Console.WriteLine("TOTAL ELEMENTS: " & aryStatistics.Length) "Total elements in array.
Console.WriteLine("ELEMENTS IN FIRST: " & aryStatistics.GetLength(0)) "Elements in first dimension.
Console.WriteLine("ELEMENTS IN SECOND: " & aryStatistics.GetLength(1)) "Elements in second dimension.
Console.WriteLine("LAST INDEX IN FIRST: " & aryStatistics.GetUpperBound(0)) "Last index in the first dimension.
Console.WriteLine("LAST INDEX IN SECOND: " & aryStatistics.GetUpperBound(1)) "Last index in the second dimension.
End Sub
End class</source>
<pre class=codeResult>RANK: 2
TOTAL ELEMENTS: 75
ELEMENTS IN FIRST: 15
ELEMENTS IN SECOND: 5
LAST INDEX IN FIRST: 14
LAST INDEX IN SECOND: 4</pre>

==Array.IndexOf==

<source lang="vbnet">public class Test

public Shared Sub Main
Dim values(10) As Integer
For i As Integer = 0 To 10
values(i) = i
Next i

Console.WriteLine(Array.IndexOf(values, 6).ToString)
End Sub

End class</source>
<pre class=codeResult>6</pre>

==Array.LastIndexOf==

<source lang="vbnet">public class Test

public Shared Sub Main
Dim values(10) As Integer
For i As Integer = 0 To 10
values(i) = i
Next i
Console.WriteLine(Array.LastIndexOf(values, 3).ToString)
End Sub

End class</source>
<pre class=codeResult>3</pre>

==Array SetValue and GetValue==

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

public Shared Sub Main
Dim squares As Array = Array.CreateInstance(GetType(Integer), 11)
For i As Integer = 0 To 10
squares.SetValue(i * i, i)
Next i
For i As Integer = 0 To 10
Console.WriteLine(squares.GetValue(i).ToString)
Next i
End Sub

End class</source>
<pre class=codeResult>0
1
4
9
16
25
36
49
64
81
100</pre>

==Copy array elements from one array to another==

<source lang="vbnet">Module Tester
Sub Main()
Dim Values() As Integer = {100, 200, 300, 400, 500}
Dim MyValues(5) As Integer
Dim Prices() As Double = {25.5, 4.95, 33.4}
Dim I As Integer
For I = 0 To 4
Console.Write(Values(I) & " ")
Next
Console.WriteLine()
" Copy one array to another
Values.CopyTo(MyValues, 0)
For I = 0 To 4
Console.Write(MyValues(I) & " ")
Next
End Sub
End Module</source>
<pre class=codeResult>100 200 300 400 500
100 200 300 400 500</pre>

==Get Enumerator from array==

<source lang="vbnet">Imports System.Collections
Module Module1

Sub Main()
Dim StringArray() As String = {"This", "is", "a", "test"}
Dim E As IEnumerator = StringArray.GetEnumerator()

While (E.MoveNext())
Console.WriteLine(E.Current())
End While

Dim AnArray(5) As Array
AnArray(0) = StringArray
Console.WriteLine(CType(AnArray(0), String())(0))

End Sub
End Module</source>
<pre class=codeResult>This
is
a
test
This</pre>

==One dimensional Array with Array.CreateInstance==

<source lang="vbnet">public class Test

public Shared Sub Main
Dim start_time As DateTime
Dim stop_time As DateTime
Dim elapsed_time As TimeSpan
Dim num_items As Integer = 10000

" One-dimensional Array.
Dim array3 As Array = _
Array.CreateInstance(GetType(Integer), num_items)
start_time = Now
For i As Integer = 0 To num_items - 1
array3.SetValue(i, i)
Next i
stop_time = Now
elapsed_time = stop_time.Subtract(start_time)
Console.WriteLine(elapsed_time.TotalSeconds())

Erase array3
End Sub

End class</source>
<pre class=codeResult>0</pre>

==Reverse array elements==

<source lang="vbnet">Module Tester
Sub Main()
Dim Values() As Integer = {100, 200, 300, 400, 500}
Dim MyValues(5) As Integer
Dim Prices() As Double = {25.5, 4.95, 33.4}
Dim I As Integer
For I = 0 To 4
Console.Write(Values(I) & " ")
Next
Console.WriteLine()
Values.Reverse(Values)
For I = 0 To 4
Console.Write(Values(I) & " ")
Next
Console.WriteLine()
End Sub
End Module</source>
<pre class=codeResult>100 200 300 400 500
500 400 300 200 100</pre>

==Two-dimensional Array with Array.CreateInstance==

<source lang="vbnet">public class Test

public Shared Sub Main
Dim start_time As DateTime
Dim stop_time As DateTime
Dim elapsed_time As TimeSpan
Dim num_items As Integer = 10000
" Two-dimensional Array.
Dim array4 As Array = _
Array.CreateInstance(GetType(Integer), 1, num_items)
start_time = Now
For i As Integer = 0 To num_items - 1
array4.SetValue(i, 0, i)
Next i
stop_time = Now
elapsed_time = stop_time.Subtract(start_time)
Console.WriteLine(elapsed_time.TotalSeconds())
Erase array4
End Sub

End class</source>
<pre class=codeResult>0</pre>

==Use Array.Sort() to sort object array==

<source lang="vbnet">Imports System
Module MyModule
Sub Main()
Dim salaries(4) As Salary
salaries(0) = New Salary(9)
salaries(1) = New Salary(4)
salaries(2) = New Salary(8)
salaries(3) = salaries(2)
salaries(4) = New Salary(6)
Console.WriteLine("Unsorted array:")
Dim salary As Salary
For Each salary In salaries
Console.WriteLine("{0}", salary)
Next
Array.Sort(salaries)
Console.WriteLine(vbCrLf & "Sorted array:")
For Each salary In salaries
Console.WriteLine("{0}", salary)
Next
End Sub
End Module
Structure Salary
Implements IComparable
Private value As Integer
Public Sub New(ByVal amount As Double)
Me.value = CInt(amount * 100)
End Sub
Public Function CompareTo(ByVal other As Object) As Integer Implements IComparable.rupareTo
Dim m2 As Salary = CType(other, Salary)
If Me.value < m2.value Then
Return -1
ElseIf Me.value = m2.value Then
Return 0
Else
Return +1
End If
End Function
Public Overrides Function ToString() As String
Return Me.value
End Function
End Structure</source>
<pre class=codeResult>Unsorted array:
900
400
800
800
600
Sorted array:
400
600
800
800
900</pre>

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в 16:40, 26 мая 2010

Admin: 1 версия