в 16:40, 26 мая 2010

2010-05-26T16:40:06Z

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2010-05-26T12:42:09Z

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==Array passed By Reference==

<source lang="vbnet">
Imports System
Public Class MainClass
Shared Sub Main(ByVal args As String())
Dim i As Integer
" declare array references
Dim secondArray As Integer()
Dim secondArrayCopy As Integer()
" allocate secondArray and copy its reference
secondArray = New Integer() {1, 2, 3}
secondArrayCopy = secondArray
Console.WriteLine(vbCrLf & "Test passing array " & _
"reference using ByRef.")
Console.Write("Contents of secondArray before " & _
"calling SecondDouble: ")
" print contents of secondArray before procedure call
For i = 0 To secondArray.GetUpperBound(0)
Console.Write(secondArray(i) & " ")
Next
" pass secondArray using ByRef
SecondDouble(secondArray)
Console.Write(vbCrLf & "Contents of secondArray " & _
"after calling SecondDouble: ")
" print contents of secondArray after procedure call
For i = 0 To secondArray.GetUpperBound(0)
Console.Write(secondArray(i) & " ")
Next
" test whether the reference was changed by SecondDouble
If secondArray Is secondArrayCopy Then
Console.WriteLine(vbCrLf & "The references are " & _
"equal.")
Else
Console.WriteLine(vbCrLf & "The references are " & _
"not equal.")
End If

End Sub
" procedure modifies elements of array and assigns
" new reference (note ByRef)
Shared Sub SecondDouble(ByRef array As Integer())
Dim i As Integer
" double contents of array
For i = 0 To array.GetUpperBound(0)
array(i) *= 2
Next
" create new reference, assign it to array
array = New Integer() {11, 12, 13}
End Sub " SecondDouble
End Class

</source>

==Modify Array Element By Reference ==

<source lang="vbnet">
Imports System
Public Class MainClass
Shared Sub Main(ByVal args As String())
Dim array1 As Integer() = New Integer() {1, 2, 3, 4, 5}
Dim i As Integer
Console.WriteLine( "The values of the original array are:" & vbCrLf )
" display original elements of array1
For i = 0 To array1.GetUpperBound(0)
Console.WriteLine( " " & array1(i) )
Next
" array element passed by reference
ModifyElementByRef(array1(3))
Console.WriteLine( vbCrLf & "array1(3) after " & _
"ModifyElementByRef: " & array1(3) )
End Sub
Shared Sub ModifyElementByRef(ByRef element As Integer)
Console.WriteLine( vbCrLf & "Value received in " & _
"ModifyElementByRef: " & element )
element *= 2
Console.WriteLine( vbCrLf & "Value calculated in " & _
"ModifyElementByRef: " & element )
End Sub " ModifyElementByRef

End Class

</source>

==Pass parameter By value or By Reference==

<source lang="vbnet">
Imports System
Imports System.Diagnostics
Public Class MainClass
Shared Sub DoubleItByVal(ByVal X As Single)
X *= 2
End Sub
Shared Sub DoubleItByRef(ByRef X As Single)
X *= 2
End Sub
Shared Sub Main()
Dim value As Single
value = 10
DoubleItByVal(value)
Console.WriteLine(value)
value = 10
DoubleItByRef(value)
Console.WriteLine(value)
End Sub
End Class

</source>

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в 16:40, 26 мая 2010

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