PropertyInfo.GetIndexParameters Metodo

public:
 abstract cli::array <System::Reflection::ParameterInfo ^> ^ GetIndexParameters();

public abstract System.Reflection.ParameterInfo[] GetIndexParameters();

abstract member GetIndexParameters : unit -> System.Reflection.ParameterInfo[]

Public MustOverride Function GetIndexParameters () As ParameterInfo()

Restituisce

Matrice di tipo ParameterInfo contenente i parametri per gli indici. Se la proprietà non è stata indicizzata, la matrice conterrà 0 (zero) elementi.

Implementazioni

Esempio

Nell'esempio seguente vengono visualizzati i parametri di indice della proprietà specificata.

using System;
using System.Reflection;

// A class that contains some properties.
public class MyProperty
{
    // Define a simple string property.
    private string caption = "A Default caption";
    public string Caption
    {
        get{return caption;}
        set {if(caption!=value) {caption = value;}
        }
    }

    // A very limited indexer that gets or sets one of four
    // strings.
    private string[] strings = {"abc", "def", "ghi", "jkl"};
    public string this[int Index]
    {
        get
        {
            return strings[Index];
        }
        set
        {
            strings[Index] = value;
        }
    }
}

class Mypropertyinfo
{
    public static int Main()
    {
        // Get the type and PropertyInfo.
        Type t = Type.GetType("MyProperty");
        PropertyInfo pi = t.GetProperty("Caption");

        // Get the public GetIndexParameters method.
        ParameterInfo[] parms = pi.GetIndexParameters();
        Console.WriteLine("\r\n" + t.FullName + "." + pi.Name
            + " has " + parms.GetLength(0) + " parameters.");

        // Display a property that has parameters. The default
        // name of an indexer is "Item".
        pi = t.GetProperty("Item");
        parms = pi.GetIndexParameters();
        Console.WriteLine(t.FullName + "." + pi.Name + " has " +
            parms.GetLength(0) + " parameters.");
        foreach( ParameterInfo p in parms )
        {
            Console.WriteLine("   Parameter: " + p.Name);
        }

        return 0;
    }
}
/*
 This example produces the following output:
 MyProperty.Caption has 0 parameters.
 MyProperty.Item has 1 parameters.
    Parameter: Index
 */

Imports System.Reflection
Imports System.Collections

' A test class that has some properties.
Public Class MyProperty

    ' Define a simple string property.
    Private myCaption As String = "A Default caption"
    Public Property Caption() As String
        Get
            Return myCaption
        End Get
        Set(ByVal Value As String)
            If myCaption <> value Then
                myCaption = value
            End If
        End Set
    End Property

    ' A very limited indexed default property that gets or
    ' sets one of four string values.
    Private strings() As String = {"abc", "def", "ghi", "jkl"}
    Public Default Property Item(ByVal Index As Integer) As String
        Get
            Return strings(Index)
        End Get
        Set
            strings(Index) = Value
        End Set 
    End Property
End Class

Public Class Example

    Public Shared Function Main() As Integer

        ' Get the type and PropertyInfo.
        Dim t As Type = GetType(MyProperty)
        Dim pi As PropertyInfo = t.GetProperty("Caption")

        ' Get an array containing the parameters (if any).
        Dim params As ParameterInfo() = pi.GetIndexParameters()
        Console.WriteLine(vbCrLf & t.FullName & "." & pi.Name & _
           " has " & params.GetLength(0) & " parameters.")

        ' Display a property that has parameters.
        pi = t.GetProperty("Item")
        params = pi.GetIndexParameters()
        Console.WriteLine(t.FullName & "." & pi.Name & _
           " has " & params.GetLength(0) & " parameters.")
        For Each p As ParameterInfo In params
            Console.WriteLine("   Parameter: " & p.Name)
        Next

        Return 0
    End Function
End Class

' This example produces the following output:
' MyProperty.Caption has 0 parameters.
' MyProperty.Item has 1 parameters.
'    Parameter: Index

Commenti

Estrarre le informazioni sui parametri necessarie dalla matrice restituita.

Per usare il GetIndexParameters metodo , ottenere prima di tutto la classe Type. Da ottenere l'oggetto TypePropertyInfo. PropertyInfoDa , usare il GetIndexParameters metodo .