в 16:40, 26 мая 2010

2010-05-26T16:40:30Z

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2010-05-26T12:53:46Z

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==Pass array==

<source lang="vbnet">Imports System
Imports Microsoft.VisualBasic
Module Test
Dim i As Integer
Public Sub AddOne(ByVal InputArray() As Integer)
For i = 0 To 3
InputArray(i) = InputArray(i) + 1
Next
End Sub
Public Sub AddTwo(ByVal InputArray() As Integer)
Dim tempArray() As Integer
tempArray = InputArray.Clone
For i = 0 To 3
tempArray(i) = tempArray(i) + 2
Next
End Sub

Sub Main()
Dim intArray() As Integer = {6, 8, 7, 6}
For i = 0 To 3
Console.WriteLine("{0}", intArray(i))
Next
AddOne(intArray)
For i = 0 To 3
Console.WriteLine("{0}", intArray(i))
Next
AddTwo(intArray)
For i = 0 To 3
Console.WriteLine("{0}", intArray(i))
Next
End Sub
End Module</source>
<pre class=codeResult>6
8
7
6
7
9
8
7
7
9
8
7</pre>

==Passing arrays and individual array elements to procedures==

<source lang="vbnet">Module Tester
Sub Main()
Dim array1 As Integer() = New Integer() {1, 2, 3, 4, 5}
Dim i As Integer
" display original elements of array1
For i = 0 To array1.GetUpperBound(0)
Console.WriteLine(array1(i))
Next
ModifyArray(array1) " array is passed by reference
Console.WriteLine("The values of the modified array are:")
" display modified elements of array1
For i = 0 To array1.GetUpperBound(0)
Console.WriteLine(array1(i))
Next
" array element passed by value
ModifyElementByVal(array1(3))
Console.WriteLine("array1(3) after " & _
"ModifyElementByVal: " & array1(3))
" array element passed by reference
ModifyElementByRef(array1(3))
Console.WriteLine("array1(3) after " & _
"ModifyElementByRef: " & array1(3))

End Sub " Main
" procedure modifies array it receives (note ByVal)
Sub ModifyArray(ByVal arrayParameter As Integer())
Dim j As Integer
For j = 0 To arrayParameter.GetUpperBound(0)
arrayParameter(j) *= 2
Next
End Sub " ModifyArray
" procedure modifies integer passed to it
" original is not be modified (note ByVal)
Sub ModifyElementByVal(ByVal element As Integer)
Console.WriteLine("Value received in " & _
"ModifyElementByVal: " & element)
element *= 2
Console.WriteLine("Value calculated in " & _
"ModifyElementByVal: " & element)
End Sub " ModifyElementByVal
" procedure modifies integer passed to it
" original is be modified (note ByRef)
Sub ModifyElementByRef(ByRef element As Integer)
Console.WriteLine("Value received in " & _
"ModifyElementByRef: " & element )
element *= 2
Console.WriteLine("Value calculated in " & _
"ModifyElementByRef: " & element)
End Sub
End Module</source>
<pre class=codeResult>1
2
3
4
5
The values of the modified array are:
2
4
6
8
10
Value received in ModifyElementByVal: 8
Value calculated in ModifyElementByVal: 16
array1(3) after ModifyElementByVal: 8
Value received in ModifyElementByRef: 8
Value calculated in ModifyElementByRef: 16
array1(3) after ModifyElementByRef: 16</pre>

==Testing the effects of passing array references using ByVal and ByRef==

<source lang="vbnet">Module Tester
Sub Main()
Dim i As Integer
Dim firstArray As Integer()
Dim firstArrayCopy As Integer()
firstArray = New Integer() {1, 2, 3}
firstArrayCopy = firstArray
For i = 0 To firstArray.GetUpperBound(0)
Console.Write(firstArray(i) & " ")
Next
FirstDouble(firstArray)
For i = 0 To firstArray.GetUpperBound(0)
Console.Write(firstArray(i) & " ")
Next
If firstArray Is firstArrayCopy Then
Console.WriteLine("The references are equal.")
Else
Console.WriteLine("The references are not equal.")
End If
Dim secondArray As Integer()
Dim secondArrayCopy As Integer()
secondArray = New Integer() {1, 2, 3}
secondArrayCopy = secondArray
For i = 0 To secondArray.GetUpperBound(0)
Console.Write(secondArray(i) & " ")
Next
SecondDouble(secondArray)
For i = 0 To secondArray.GetUpperBound(0)
Console.Write(secondArray(i) & " ")
Next
If secondArray Is secondArrayCopy Then
Console.WriteLine("The references are equal.")
Else
Console.WriteLine("The references are not equal.")
End If
End Sub " Main
Sub FirstDouble(ByVal array As Integer())
Dim i As Integer
For i = 0 To array.GetUpperBound(0)
array(i) *= 2
Next
array = New Integer() {11, 12, 13}
End Sub
Sub SecondDouble(ByRef array As Integer())
Dim i As Integer
For i = 0 To array.GetUpperBound(0)
array(i) *= 2
Next
array = New Integer() {11, 12, 13}
End Sub
End Module</source>
<pre class=codeResult>1 2 3 2 4 6 The references are equal.
1 2 3 11 12 13 The references are not equal.</pre>

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в 16:40, 26 мая 2010

Admin: 1 версия