Visual Basic
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Setting Upper and Lower Bounds
When declaring an array, follow the array name by the upper bound in parentheses. The upper bound cannot exceed the range of a Long data type (-2,147,483,648 to 2,147,483,647). For example, these array declarations can appear in the Declarations section of a module:
Dim Counters(14) As Integer ' 15 elements.
Dim Sums(20) As Double ' 21 elements.
To create a public array, you simply use Public in place of Dim:
Public Counters(14) As Integer
Public Sums(20) As Double
The same declarations within a procedure use Dim:
Dim Counters(14) As Integer
Dim Sums(20) As Double
The first declaration creates an array with 15 elements, with index numbers running from 0 to 14. The second creates an array with 21 elements, with index numbers running from 0 to 20. The default lower bound is 0.
To specify a lower bound, provide it explicitly (as a Long data type) using the To keyword:
Dim Counters(1 To 15) As Integer
Dim Sums(100 To 120) As String
In the preceding declarations, the index numbers of Counters range from 1 to 15, and the index numbers of Sums range from 100 to 120.
Arrays that Contain Other Arrays
It's possible to create a Variant array, and populate it with other arrays of different data types. The following code creates two arrays, one containing integers and the other strings. It then declares a third Variant array and populates it with the integer and string arrays.
Private Sub Command1_Click
Dim intX As Integer ' Declare counter variable.
' Declare and populate an integer array.
Dim countersA(5) As Integer
For intX = 0 To 4
countersA(intX) = 5
Next intX
' Declare and populate a string array.
Dim countersB(5) As String
For intX = 0 To 4
countersB(intX) = "hello"
Next intX
Dim arrX(2) As Variant ' Declare a new two-member
' array.
arrX(1) = countersA ' Populate the array with
' other arrays.
arrX(2) = countersB
MsgBox arrX(12) ' Display a member of each
' array.
MsgBox arrX(23)
End Sub
Multidimensional Arrays
Sometimes you need to keep track of related information in an array. For example, to keep track of each pixel on your computer screen, you need to refer to its X and Y coordinates. This can be done using a multidimensional array to store the values.
With Visual Basic, you can declare arrays of multiple dimensions. For example, the following statement declares a two-dimensional 10-by-10 array within a procedure:
Static MatrixA(9, 9) As Double
Either or both dimensions can be declared with explicit lower bounds:
Static MatrixA(1 To 10, 1 To 10) As Double
You can extend this to more than two dimensions. For example:
Dim MultiD(3, 1 To 10, 1 To 15)
This declaration creates an array that has three dimensions with sizes 4 by 10 by 15. The total number of elements is the product of these three dimensions, or 600.
Note When you start adding dimensions to an array, the total storage needed by the array increases dramatically, so use multidimensional arrays with care. Be especially careful with Variant arrays, because they are larger than other data types.
Using Loops to Manipulate Arrays
You can efficiently process a multidimensional array by using nested For loops. For example, these statements initialize every element in MatrixA to a value based on its location in the array:
Dim I As Integer, J As Integer
Static MatrixA(1 To 10, 1 To 10) As Double
For I = 1 To 10
For J = 1 To 10
MatrixA(I, J) = I * 10 + J
Next J
Next I
When declaring an array, follow the array name by the upper bound in parentheses. The upper bound cannot exceed the range of a Long data type (-2,147,483,648 to 2,147,483,647). For example, these array declarations can appear in the Declarations section of a module:
Dim Counters(14) As Integer ' 15 elements.
Dim Sums(20) As Double ' 21 elements.
To create a public array, you simply use Public in place of Dim:
Public Counters(14) As Integer
Public Sums(20) As Double
The same declarations within a procedure use Dim:
Dim Counters(14) As Integer
Dim Sums(20) As Double
The first declaration creates an array with 15 elements, with index numbers running from 0 to 14. The second creates an array with 21 elements, with index numbers running from 0 to 20. The default lower bound is 0.
To specify a lower bound, provide it explicitly (as a Long data type) using the To keyword:
Dim Counters(1 To 15) As Integer
Dim Sums(100 To 120) As String
In the preceding declarations, the index numbers of Counters range from 1 to 15, and the index numbers of Sums range from 100 to 120.
Arrays that Contain Other Arrays
It's possible to create a Variant array, and populate it with other arrays of different data types. The following code creates two arrays, one containing integers and the other strings. It then declares a third Variant array and populates it with the integer and string arrays.
Private Sub Command1_Click
Dim intX As Integer ' Declare counter variable.
' Declare and populate an integer array.
Dim countersA(5) As Integer
For intX = 0 To 4
countersA(intX) = 5
Next intX
' Declare and populate a string array.
Dim countersB(5) As String
For intX = 0 To 4
countersB(intX) = "hello"
Next intX
Dim arrX(2) As Variant ' Declare a new two-member
' array.
arrX(1) = countersA ' Populate the array with
' other arrays.
arrX(2) = countersB
MsgBox arrX(12) ' Display a member of each
' array.
MsgBox arrX(23)
End Sub
Multidimensional Arrays
Sometimes you need to keep track of related information in an array. For example, to keep track of each pixel on your computer screen, you need to refer to its X and Y coordinates. This can be done using a multidimensional array to store the values.
With Visual Basic, you can declare arrays of multiple dimensions. For example, the following statement declares a two-dimensional 10-by-10 array within a procedure:
Static MatrixA(9, 9) As Double
Either or both dimensions can be declared with explicit lower bounds:
Static MatrixA(1 To 10, 1 To 10) As Double
You can extend this to more than two dimensions. For example:
Dim MultiD(3, 1 To 10, 1 To 15)
This declaration creates an array that has three dimensions with sizes 4 by 10 by 15. The total number of elements is the product of these three dimensions, or 600.
Note When you start adding dimensions to an array, the total storage needed by the array increases dramatically, so use multidimensional arrays with care. Be especially careful with Variant arrays, because they are larger than other data types.
Using Loops to Manipulate Arrays
You can efficiently process a multidimensional array by using nested For loops. For example, these statements initialize every element in MatrixA to a value based on its location in the array:
Dim I As Integer, J As Integer
Static MatrixA(1 To 10, 1 To 10) As Double
For I = 1 To 10
For J = 1 To 10
MatrixA(I, J) = I * 10 + J
Next J
Next I
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zaraz_ka
как делать массивы в Visual Basic ?