VB.Net Tutorial/Collections/Multiple dimensional array
Содержание
- 1 Declare the jagged array as 4 rows high
- 2 Define and initialize the two dimensional array
- 3 Initialize two dimensional array by index
- 4 Initializing multi-dimensional arrays
- 5 Jagged two-dimensional array example.
- 6 Rectangular Array
- 7 Reference elements in two dimensional array
- 8 Set the array of arrays
- 9 Use For Each/Next to find an element in a two dimension array
Declare the jagged array as 4 rows high
<source lang="vbnet">Option Strict On
Imports System
Public Class Tester
Public Shared Sub Main()
Const rowsUB As Integer = 3 " upper bounds
Const rowZero As Integer = 5
Const rowOne As Integer = 2
Const rowTwo As Integer = 3
Const rowThree As Integer = 5
Dim i As Integer
Dim jaggedArray(rowsUB)() As Integer
ReDim jaggedArray(0)(rowZero)
ReDim jaggedArray(1)(rowOne)
ReDim jaggedArray(2)(rowTwo)
ReDim jaggedArray(3)(rowThree)
jaggedArray(0)(3) = 15
jaggedArray(1)(1) = 12
jaggedArray(2)(1) = 9
jaggedArray(2)(2) = 99
jaggedArray(3)(0) = 10
jaggedArray(3)(1) = 11
jaggedArray(3)(2) = 12
jaggedArray(3)(3) = 13
jaggedArray(3)(4) = 14
For i = 0 To rowZero
Console.WriteLine("jaggedArray(0)({0}) = {1}", _
i, jaggedArray(0)(i))
Next
For i = 0 To rowOne
Console.WriteLine("jaggedArray(1)({0}) = {1}", _
i, jaggedArray(1)(i))
Next
For i = 0 To rowTwo
Console.WriteLine("jaggedArray(2)({0}) = {1}", _
i, jaggedArray(2)(i))
Next
For i = 0 To rowThree
Console.WriteLine("jaggedArray(3)({0}) = {1}", _
i, jaggedArray(3)(i))
Next
End Sub
End Class</source>
jaggedArray(0)(0) = 0 jaggedArray(0)(1) = 0 jaggedArray(0)(2) = 0 jaggedArray(0)(3) = 15 jaggedArray(0)(4) = 0 jaggedArray(0)(5) = 0 jaggedArray(1)(0) = 0 jaggedArray(1)(1) = 12 jaggedArray(1)(2) = 0 jaggedArray(2)(0) = 0 jaggedArray(2)(1) = 9 jaggedArray(2)(2) = 99 jaggedArray(2)(3) = 0 jaggedArray(3)(0) = 10 jaggedArray(3)(1) = 11 jaggedArray(3)(2) = 12 jaggedArray(3)(3) = 13 jaggedArray(3)(4) = 14 jaggedArray(3)(5) = 0
Define and initialize the two dimensional array
<source lang="vbnet">Imports System Class Tester
Public Shared Sub Main()
Const rowsUB As Integer = 4
Const columnsUB As Integer = 3
Dim rectangularArray As Integer(,) = _
{{0, 1, 2}, {3, 4, 5}, {6, 7, 8}, {9, 10, 11}}
Dim i As Integer
For i = 0 To rowsUB - 1
Dim j As Integer
For j = 0 To columnsUB - 1
Console.WriteLine( _
"rectangularArray[{0},{1}] = {2}", _
i, j, rectangularArray(i, j))
Next j
Next i
End Sub "Run
End Class</source>
rectangularArray[0,0] = 0 rectangularArray[0,1] = 1 rectangularArray[0,2] = 2 rectangularArray[1,0] = 3 rectangularArray[1,1] = 4 rectangularArray[1,2] = 5 rectangularArray[2,0] = 6 rectangularArray[2,1] = 7 rectangularArray[2,2] = 8 rectangularArray[3,0] = 9 rectangularArray[3,1] = 10 rectangularArray[3,2] = 11
Initialize two dimensional array by index
<source lang="vbnet">Public Class Tester
Public Shared Sub Main
Dim SqaresTable(5, 1) As Integer
SqaresTable(0, 0) = 0
SqaresTable(0, 1) = 0
SqaresTable(1, 0) = 1
SqaresTable(1, 1) = 1
SqaresTable(2, 0) = 2
SqaresTable(2, 1) = 4
SqaresTable(3, 0) = 3
SqaresTable(3, 1) = 9
SqaresTable(4, 0) = 4
SqaresTable(4, 1) = 16
SqaresTable(5, 0) = 5
SqaresTable(5, 1) = 25
Console.WriteLine(SqaresTable(2, 1))
End Sub
End Class</source>
4
Initializing multi-dimensional arrays
<source lang="vbnet">Module Tester
Sub Main()
Dim i, j As Integer
" create rectangular two-dimensional array
Dim array1 As Integer(,)
array1 = New Integer(,) {{1, 2, 3}, {4, 5, 6}}
" create jagged two-dimensional array
Dim array2 As Integer()() = New Integer(2)() {}
array2(0) = New Integer() {1, 2}
array2(1) = New Integer() {3}
array2(2) = New Integer() {4, 5, 6}
For i = 0 To array1.GetUpperBound(0)
For j = 0 To array1.GetUpperBound(1)
Console.Write(array1(i, j) & " ")
Next
Console.WriteLine("")
Next
For i = 0 To array2.GetUpperBound(0)
For j = 0 To array2(i).GetUpperBound(0)
Console.WriteLine(array2(i)(j) & " ")
Next
Console.WriteLine("")
Next
End Sub
End Module</source>
1 2 3 4 5 6 1 2 3 4 5 6
Jagged two-dimensional array example.
<source lang="vbnet">Module Tester
Dim lastStudent, lastExam As Integer
Sub Main()
Dim i As Integer
" jagged array with 3 rows of exam scores
Dim gradeArray As Integer()() = New Integer(2)() {}
gradeArray(0) = New Integer() {7, 8, 6, 3}
gradeArray(1) = New Integer() {8, 7, 9, 1}
gradeArray(2) = New Integer() {0, 0, 6, 1}
" upper bounds for array manipulations
lastStudent = gradeArray.GetUpperBound(0)
lastExam = gradeArray(0).GetUpperBound(0)
Console.WriteLine("Lowest grade: " & _
Minimum(gradeArray) & vbCrLf & "Highest grade: " & _
Maximum(gradeArray))
For i = 0 To lastStudent
Console.WriteLine("Average for student " & _
i & " is " & Average(gradeArray(i)))
Next
End Sub " Main
Function Minimum(ByVal grades As Integer()()) _
As Integer
Dim lowGrade As Integer = 100
Dim i, j As Integer
For i = 0 To lastStudent
For j = 0 To lastExam
If grades(i)(j) < lowGrade Then
lowGrade = grades(i)(j)
End If
Next
Next
Return lowGrade
End Function " Minimum
Function Maximum(ByVal grades As Integer()()) _
As Integer
Dim highGrade As Integer = 0
Dim i, j As Integer
For i = 0 To lastStudent
For j = 0 To lastExam
If grades(i)(j) > highGrade Then
highGrade = grades(i)(j)
End If
Next
Next
Return highGrade
End Function " Maximum
Function Average(ByVal setOfGrades As Integer()) _
As Double
Dim i As Integer, total As Integer = 0
For i = 0 To lastExam
total += setOfGrades(i)
Next
Return total / setOfGrades.Length
End Function " Average
End Module</source>
Lowest grade: 0 Highest grade: 9 Average for student 0 is 6 Average for student 1 is 6.25 Average for student 2 is 1.75
Rectangular Array
<source lang="vbnet">Option Strict On
Imports System
Class Tester
Shared Sub Main()
Const rowsUB As Integer = 4
Const columnsUB As Integer = 3
Dim rectangularArray(rowsUB, columnsUB) As Integer
Dim i As Integer
For i = 0 To rowsUB - 1
Dim j As Integer
For j = 0 To columnsUB - 1
rectangularArray(i, j) = i + j
Next j
Next i
For i = 0 To rowsUB - 1
Dim j As Integer
For j = 0 To columnsUB - 1
Console.WriteLine( _
"rectangularArray[{0},{1}] = {2}", _
i, j, rectangularArray(i, j))
Next j
Next i
End Sub
End Class</source>
rectangularArray[0,0] = 0 rectangularArray[0,1] = 1 rectangularArray[0,2] = 2 rectangularArray[1,0] = 1 rectangularArray[1,1] = 2 rectangularArray[1,2] = 3 rectangularArray[2,0] = 2 rectangularArray[2,1] = 3 rectangularArray[2,2] = 4 rectangularArray[3,0] = 3 rectangularArray[3,1] = 4 rectangularArray[3,2] = 5
Reference elements in two dimensional array
<source lang="vbnet">public class Test
public Shared Sub Main
Dim aryBoard(9, 9) As Integer
"Move the element.
aryBoard(0, 0) = 0
aryBoard(2, 4) = 1
"Check for the element.
If aryBoard(0, 0) = 1 Then
Console.WriteLine("The piece was found.")
Else
Console.WriteLine("The piece was not found.")
End If
End Sub
End class</source>
The piece was not found.
Set the array of arrays
<source lang="vbnet">public class Test
public Shared Sub Main
Dim aryIntArray(9) As Integer
Dim aryStrArray(99) As String
Dim aryBigArray(1) As Object
Dim intCounter As Integer
"Populate array aryIntArray.
For intCounter = 0 To 9
aryIntArray(intCounter) = intCounter
Next
"Populate array aryStrArray.
For intCounter = 0 To 99
aryStrArray(intCounter) = "ITEM: " & intCounter.ToString("0000")
Next
"Set the array of arrays.
aryBigArray(0) = aryIntArray
aryBigArray(1) = aryStrArray
"Display some array values.
Console.WriteLine(aryBigArray(0)(7))
Console.WriteLine(aryBigArray(1)(16))
End Sub
End class</source>
7 ITEM: 0016
Use For Each/Next to find an element in a two dimension array
<source lang="vbnet">Module modForEach
Sub Main()
Dim gradeArray As Integer(,) = New Integer(,) _
{{77, 68, 86, 73}, {98, 87, 89, 81}, {70, 90, 86, 81}}
Dim grade As Integer
Dim lowGrade As Integer = 100
For Each grade In gradeArray
If grade < lowGrade Then
lowGrade = grade
End If
Next
Console.WriteLine("The minimum grade is: {0}", lowGrade)
End Sub " Main
End Module</source>
The minimum grade is: 68
