Array.GetLowerBound(Int32) Metodo
Definizione
Importante
Alcune informazioni sono relative alla release non definitiva del prodotto, che potrebbe subire modifiche significative prima della release definitiva. Microsoft non riconosce alcuna garanzia, espressa o implicita, in merito alle informazioni qui fornite.
Ottiene l'indice del primo elemento della dimensione specificata nella matrice.
public:
int GetLowerBound(int dimension);public int GetLowerBound (int dimension);member this.GetLowerBound : int -> intPublic Function GetLowerBound (dimension As Integer) As IntegerParametri
- dimension
- Int32
Dimensione in base zero della matrice di cui è necessario determinare l'indice iniziale.
Restituisce
Indice del primo elemento della dimensione specificata nella matrice.
Eccezioni
Esempio
Nell'esempio seguente vengono utilizzati i GetLowerBound metodi e GetUpperBound per visualizzare i limiti di una matrice unidimensionale e bidimensionale e per visualizzare i valori dei relativi elementi di matrice.
using namespace System;
void main()
{
// Create a one-dimensional integer array.
array<int>^ integers = { 2, 4, 6, 8, 10, 12, 14, 16, 18, 20 };
// Get the upper and lower bound of the array.
int upper = integers->GetUpperBound(0);
int lower = integers->GetLowerBound(0);
Console::WriteLine("Elements from index {0} to {1}:", lower, upper);
// Iterate the array.
for (int ctr = lower; ctr <= upper; ctr++)
Console::Write("{0}{1}{2}", ctr == lower ? " " : "",
integers[ctr],
ctr < upper ? ", " : Environment::NewLine);
Console::WriteLine();
// Create a two-dimensional integer array.
array<int, 2>^ integers2d = { {2, 4}, {3, 9}, {4, 16}, {5, 25},
{6, 36}, {7, 49}, {8, 64}, {9, 81} };
// Get the number of dimensions.
int rank = integers2d->Rank;
Console::WriteLine("Number of dimensions: {0}", rank);
for (int ctr = 0; ctr < rank; ctr++)
Console::WriteLine(" Dimension {0}: from {1} to {2}",
ctr, integers2d->GetLowerBound(ctr),
integers2d->GetUpperBound(ctr));
// Iterate the 2-dimensional array and display its values.
Console::WriteLine(" Values of array elements:");
for (int outer = integers2d->GetLowerBound(0); outer <= integers2d->GetUpperBound(0);
outer++)
for (int inner = integers2d->GetLowerBound(1); inner <= integers2d->GetUpperBound(1);
inner++)
Console::WriteLine(" {3}{0}, {1}{4} = {2}", outer, inner,
integers2d->GetValue(outer, inner), "{", "}");
}
// The example displays the following output:
// Elements from index 0 to 9:
// 2, 4, 6, 8, 10, 12, 14, 16, 18, 20
//
// Number of dimensions: 2
// Dimension 0: from 0 to 7
// Dimension 1: from 0 to 1
// Values of array elements:
// {0, 0} = 2
// {0, 1} = 4
// {1, 0} = 3
// {1, 1} = 9
// {2, 0} = 4
// {2, 1} = 16
// {3, 0} = 5
// {3, 1} = 25
// {4, 0} = 6
// {4, 1} = 36
// {5, 0} = 7
// {5, 1} = 49
// {6, 0} = 8
// {6, 1} = 64
// {7, 0} = 9
// {7, 1} = 81
using System;
public class Example
{
public static void Main()
{
// Create a one-dimensional integer array.
int[] integers = { 2, 4, 6, 8, 10, 12, 14, 16, 18, 20 };
// Get the upper and lower bound of the array.
int upper = integers.GetUpperBound(0);
int lower = integers.GetLowerBound(0);
Console.WriteLine($"Elements from index {lower} to {upper}:");
// Iterate the array.
for (int ctr = lower; ctr <= upper; ctr++)
Console.Write($"{(ctr == lower ?" " : "")}{integers[ctr]}" +
$"{(ctr < upper ? ", " : Environment.NewLine)}");
Console.WriteLine();
// Create a two-dimensional integer array.
int[,] integers2d= { {2, 4}, {3, 9}, {4, 16}, {5, 25},
{6, 36}, {7, 49}, {8, 64}, {9, 81} };
// Get the number of dimensions.
int rank = integers2d.Rank;
Console.WriteLine($"Number of dimensions: {rank}");
for (int ctr = 0; ctr < rank; ctr++)
Console.WriteLine($" Dimension {ctr}: " +
$"from {integers2d.GetLowerBound(ctr)} to {integers2d.GetUpperBound(ctr)}");
// Iterate the 2-dimensional array and display its values.
Console.WriteLine(" Values of array elements:");
for (int outer = integers2d.GetLowerBound(0); outer <= integers2d.GetUpperBound(0);
outer++)
for (int inner = integers2d.GetLowerBound(1); inner <= integers2d.GetUpperBound(1);
inner++)
Console.WriteLine($" {'\u007b'}{outer}, {inner}{'\u007d'} = " +
$"{integers2d.GetValue(outer, inner)}");
}
}
// The example displays the following output:
// Elements from index 0 to 9:
// 2, 4, 6, 8, 10, 12, 14, 16, 18, 20
//
// Number of dimensions: 2
// Dimension 0: from 0 to 7
// Dimension 1: from 0 to 1
// Values of array elements:
// {0, 0} = 2
// {0, 1} = 4
// {1, 0} = 3
// {1, 1} = 9
// {2, 0} = 4
// {2, 1} = 16
// {3, 0} = 5
// {3, 1} = 25
// {4, 0} = 6
// {4, 1} = 36
// {5, 0} = 7
// {5, 1} = 49
// {6, 0} = 8
// {6, 1} = 64
// {7, 0} = 9
// {7, 1} = 81
open System
// Create a one-dimensional integer array.
let integers = [| 2..2..20 |]
// Get the upper and lower bound of the array.
let upper = integers.GetUpperBound 0
let lower = integers.GetLowerBound 0
printfn $"Elements from index {lower} to {upper}:"
// Iterate the array.
for i = lower to upper do
if i = lower then printf " "
printf $"{integers[i]}"
if i < upper then ", " else Environment.NewLine
|> printf "%s"
printfn ""
// Create a two-dimensional integer array.
let integers2d =
array2D [ [ 2; 4 ]; [ 3; 9 ]; [ 4; 16 ]; [ 5; 25 ]
[ 6; 36 ]; [ 7; 49 ]; [ 8; 64 ]; [ 9; 81 ] ]
// Get the number of dimensions.
let rank = integers2d.Rank
printfn $"Number of dimensions: {rank}"
for i = 0 to rank - 1 do
printfn $" Dimension {i}: from {integers2d.GetLowerBound i} to {integers2d.GetUpperBound i}"
// Iterate the 2-dimensional array and display its values.
printfn " Values of array elements:"
for outer = integers2d.GetLowerBound 0 to integers2d.GetUpperBound 0 do
for inner = integers2d.GetLowerBound 1 to integers2d.GetUpperBound 1 do
printfn $" {'\u007b'}{outer}, {inner}{'\u007d'} = {integers2d.GetValue(outer, inner)}"
// The example displays the following output:
// Elements from index 0 to 9:
// 2, 4, 6, 8, 10, 12, 14, 16, 18, 20
//
// Number of dimensions: 2
// Dimension 0: from 0 to 7
// Dimension 1: from 0 to 1
// Values of array elements:
// {0, 0} = 2
// {0, 1} = 4
// {1, 0} = 3
// {1, 1} = 9
// {2, 0} = 4
// {2, 1} = 16
// {3, 0} = 5
// {3, 1} = 25
// {4, 0} = 6
// {4, 1} = 36
// {5, 0} = 7
// {5, 1} = 49
// {6, 0} = 8
// {6, 1} = 64
// {7, 0} = 9
// {7, 1} = 81
Public Module Example
Public Sub Main()
' Create a one-dimensional integer array.
Dim integers() As Integer = { 2, 4, 6, 8, 10, 12, 14, 16, 18, 20 }
' Get the upper and lower bound of the array.
Dim upper As Integer = integers.GetUpperBound(0)
Dim lower As Integer = integers.GetLowerBound(0)
Console.WriteLine($"Elements from index {lower} to {upper}:")
' Iterate the array.
For ctr As Integer = lower To upper
Console.Write("{0}{1}{2}", If(ctr = lower, " ", ""),
integers(ctr),
If(ctr < upper, ", ", vbCrLf))
Next
Console.WriteLine()
' Create a two-dimensional integer array.
Dim integers2d(,) As Integer = {{2, 4}, {3, 9}, {4, 16}, {5, 25},
{6, 36}, {7, 49}, {8, 64}, {9, 81} }
' Get the number of dimensions.
Dim rank As Integer = integers2d.Rank
Console.WriteLine($"Number of dimensions: {rank}")
For ctr As Integer = 0 To rank - 1
Console.WriteLine($" Dimension {ctr}: " +
$"from {integers2d.GetLowerBound(ctr)} to {integers2d.GetUpperBound(ctr)}")
Next
' Iterate the 2-dimensional array and display its values.
Console.WriteLine(" Values of array elements:")
For outer = integers2d.GetLowerBound(0) To integers2d.GetUpperBound(0)
For inner = integers2d.GetLowerBound(1) To integers2d.GetUpperBound(1)
Console.WriteLine($" {ChrW(&h07b)}{outer}, {inner}{ChrW(&h007d)} = " +
$"{integers2d.GetValue(outer, inner)}")
Next
Next
End Sub
End Module
' The example displays the following output.
' Elements from index 0 to 9:
' 2, 4, 6, 8, 10, 12, 14, 16, 18, 20
'
' Number of dimensions: 2
' Dimension 0: from 0 to 7
' Dimension 1: from 0 to 1
' Values of array elements:
' {0, 0} = 2
' {0, 1} = 4
' {1, 0} = 3
' {1, 1} = 9
' {2, 0} = 4
' {2, 1} = 16
' {3, 0} = 5
' {3, 1} = 25
' {4, 0} = 6
' {4, 1} = 36
' {5, 0} = 7
' {5, 1} = 49
' {6, 0} = 8
' {6, 1} = 64
' {7, 0} = 9
' {7, 1} = 81
Commenti
GetLowerBound(0) restituisce l'indice iniziale della prima dimensione della matrice e GetLowerBound(Rank - 1) restituisce l'indice iniziale dell'ultima dimensione della matrice.
Il GetLowerBound metodo restituisce sempre un valore che indica l'indice del limite inferiore della matrice, anche se la matrice è vuota.
Si noti che, anche se la maggior parte delle matrici in .NET è basata su zero, ovvero il GetLowerBound metodo restituisce zero per ogni dimensione di una matrice, .NET supporta matrici non basate su zero. Tali matrici possono essere create con il CreateInstance(Type, Int32[], Int32[]) metodo e possono anche essere restituite da codice non gestito.
Questo metodo è un'operazione O(1).