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Environment.GetEnvironmentVariables Metodo

Definizione

Recupera tutti i nomi delle variabili di ambiente e i rispettivi valori.

Overload

GetEnvironmentVariables()

Recupera tutti i nomi delle variabili di ambiente e i rispettivi valori dal processo corrente.

GetEnvironmentVariables(EnvironmentVariableTarget)

Recupera tutti i nomi delle variabili di ambiente e i rispettivi valori dal processo corrente o dalla chiave del Registro del sistema operativo Windows per l'utente corrente o per il computer locale.

GetEnvironmentVariables()

Origine:
Environment.Variables.Windows.cs
Origine:
Environment.Variables.Windows.cs
Origine:
Environment.Variables.Windows.cs

Recupera tutti i nomi delle variabili di ambiente e i rispettivi valori dal processo corrente.

public:
 static System::Collections::IDictionary ^ GetEnvironmentVariables();
public static System.Collections.IDictionary GetEnvironmentVariables ();
static member GetEnvironmentVariables : unit -> System.Collections.IDictionary
Public Shared Function GetEnvironmentVariables () As IDictionary

Restituisce

Dizionario contenente tutti i nomi delle variabili di ambiente e i rispettivi valori, se presenti; in caso contrario, se non viene trovata alcuna variabile di ambiente, verrà restituito un dizionario vuoto.

Eccezioni

Il chiamante non ha l'autorizzazione richiesta per eseguire questa operazione.

La memoria del buffer è insufficiente.

Esempio

Nell'esempio seguente viene illustrato il GetEnvironmentVariables metodo.

using namespace System;
using namespace System::Collections;

int main()
{
   Console::WriteLine( "GetEnvironmentVariables: " );
   for each (DictionaryEntry^ de in Environment::GetEnvironmentVariables())
      Console::WriteLine( " {0} = {1}", de->Key, de->Value );
}
// Output from the example is not shown, since it is:
//    Lengthy.
//    Specific to the machine on which the example is run.
//    May reveal information that should remain secure.
// Sample for the Environment.GetEnvironmentVariables method
using System;
using System.Collections;

class Sample
{
    public static void Main()
    {
       Console.WriteLine();
       Console.WriteLine("GetEnvironmentVariables: ");
       foreach (DictionaryEntry de in Environment.GetEnvironmentVariables())
           Console.WriteLine("  {0} = {1}", de.Key, de.Value);
    }
}
// Output from the example is not shown, since it is:
//    Lengthy.
//    Specific to the machine on which the example is run.
//    May reveal information that should remain secure.
// Sample for the Environment.GetEnvironmentVariables method
open System
open System.Collections

printfn "\nGetEnvironmentVariables: "
for de in Environment.GetEnvironmentVariables() do
    let de = de :?> DictionaryEntry
    printfn $"  {de.Key} = {de.Value}"
// Output from the example is not shown, since it is:
//    Lengthy.
//    Specific to the machine on which the example is run.
//    May reveal information that should remain secure.
' Sample for the Environment.GetEnvironmentVariables method
Imports System.Collections

Class Sample
   Public Shared Sub Main()
      Console.WriteLine("GetEnvironmentVariables: ")
      For Each de As DictionaryEntry In Environment.GetEnvironmentVariables()
         Console.WriteLine("  {0} = {1}", de.Key, de.Value)
      Next 
   End Sub 
End Class 
' Output from the example is not shown, since it is:
'    Lengthy.
'    Specific to the machine on which the example is run.
'    May reveal information that should remain secure.

Commenti

I nomi e i valori per le variabili di ambiente vengono archiviati come coppie chiave-valore nell'oggetto restituito IDictionary.

Nei sistemi Windows

Nei sistemi Windows il GetEnvironmentVariables metodo restituisce le variabili di ambiente seguenti:

Nei sistemi unix

Nei sistemi Unix, il GetEnvironmentVariables metodo recupera il nome e il valore di tutte le variabili di ambiente ereditate dal processo padre che ha avviato il dotnet processo o che vengono definiti nell'ambito del dotnet processo stesso. Al termine del dotnet processo, queste ultime variabili di ambiente non possono esistere.

.NET in esecuzione nei sistemi unix non supporta variabili di ambiente per computer o per utente.

Nota

Nei sistemi Unix, le modifiche dell'ambiente in-process apportate dalle librerie native non vengono visualizzate dai chiamanti gestiti.

Vedi anche

Si applica a

GetEnvironmentVariables(EnvironmentVariableTarget)

Origine:
Environment.cs
Origine:
Environment.cs
Origine:
Environment.cs

Recupera tutti i nomi delle variabili di ambiente e i rispettivi valori dal processo corrente o dalla chiave del Registro del sistema operativo Windows per l'utente corrente o per il computer locale.

public:
 static System::Collections::IDictionary ^ GetEnvironmentVariables(EnvironmentVariableTarget target);
public static System.Collections.IDictionary GetEnvironmentVariables (EnvironmentVariableTarget target);
static member GetEnvironmentVariables : EnvironmentVariableTarget -> System.Collections.IDictionary
Public Shared Function GetEnvironmentVariables (target As EnvironmentVariableTarget) As IDictionary

Parametri

target
EnvironmentVariableTarget

Uno dei valori di EnvironmentVariableTarget. È supportato solo Process in .NET in esecuzione nei sistemi unix.

Restituisce

Dizionario contenente tutti i nomi delle variabili di ambiente e i rispettivi valori ricavati dall'origine specificata dal parametro target, se presenti; in caso contrario, se non viene trovata alcuna variabile di ambiente, verrà restituito un dizionario vuoto.

Eccezioni

Il chiamante non ha l'autorizzazione richiesta per eseguire questa operazione per il valore specificato di target.

target contiene un valore non valido.

Esempio

Nell'esempio seguente vengono create variabili di ambiente per le EnvironmentVariableTarget.Processdestinazioni , EnvironmentVariableTarget.Usere Machine verifica se il Registro di sistema operativo contiene le variabili di ambiente utente e computer, quindi elimina le variabili di ambiente. Poiché i sistemi .NET in unix non supportano variabili di ambiente per utente e per computer, solo SetEnvironmentVariable(String, String) e SetEnvironmentVariable(String, String, EnvironmentVariableTarget) con un valore di archiviare correttamente una variabile di EnvironmentVariableTarget.Process ambiente al blocco di ambiente di processo.

using System;
using System.Collections;
using Microsoft.Win32;

class Sample
{
    public static void Main()
    {
        // Environment variable names for default, process, user, and machine targets.
        string defaultEnvVar = nameof(defaultEnvVar);
        string processEnvVar = nameof(processEnvVar);
        string userEnvVar = nameof(userEnvVar);
        string machineEnvVar = nameof(machineEnvVar);

        string dft = nameof(dft);
        string process = nameof(process);
        string user = nameof(user);
        string machine = nameof(machine);

        // Set the environment variable for each target.
        Console.WriteLine("Setting environment variables for each target...\n");
        // The default target (the current process).
        Environment.SetEnvironmentVariable(defaultEnvVar, dft);
        // The current process.
        Environment.SetEnvironmentVariable(processEnvVar, process,
                                           EnvironmentVariableTarget.Process);
        // The current user.
        Environment.SetEnvironmentVariable(userEnvVar, user,
                                           EnvironmentVariableTarget.User);
        // The local machine.
        Environment.SetEnvironmentVariable(machineEnvVar, machine,
                                           EnvironmentVariableTarget.Machine);

        // Define an array of environment variables.
        string[] envVars = { defaultEnvVar,processEnvVar, userEnvVar, machineEnvVar };

        // Try to get the environment variables from each target.
        // The default (no specified target).
        Console.WriteLine("Retrieving environment variables from the default target:");
        foreach (var envVar in envVars)
        {
          var value = Environment.GetEnvironmentVariable(envVar) ?? "(none)";
          Console.WriteLine($"   {envVar}: {value}");
        }
        // The process block.
        Console.WriteLine("\nRetrieving environment variables from the Process target:");
        foreach (var envVar in envVars)
        {
          var value = Environment.GetEnvironmentVariable(envVar, EnvironmentVariableTarget.Process) ?? "(none)";
          Console.WriteLine($"   {envVar}: {value}");
        }
        // The user block.
        Console.WriteLine("\nRetrieving environment variables from the User target:");
        foreach (var envVar in envVars)
        {
          var value = Environment.GetEnvironmentVariable(envVar, EnvironmentVariableTarget.User) ?? "(none)";
          Console.WriteLine($"   {envVar}: {value}");
        }
        // The machine block.
        Console.WriteLine("\nRetrieving environment variables from the Machine target:");
        foreach (var envVar in envVars)
        {
          var value = Environment.GetEnvironmentVariable(envVar, EnvironmentVariableTarget.Machine) ?? "(none)";
          Console.WriteLine($"   {envVar}: {value}");
        }

        // Delete the environment variable for each target.
        Console.WriteLine("\nDeleting environment variables for each target...\n");
        // The default target (the current process).
        Environment.SetEnvironmentVariable(defaultEnvVar, null);
        // The current process.
        Environment.SetEnvironmentVariable(processEnvVar, null,
                                           EnvironmentVariableTarget.Process);
        // The current user.
        Environment.SetEnvironmentVariable(userEnvVar, null,
                                           EnvironmentVariableTarget.User);
        // The local machine.
        Environment.SetEnvironmentVariable(machineEnvVar, null,
                                           EnvironmentVariableTarget.Machine);
    }
}
// The example displays the following output if run on a Windows system:
//      Setting environment variables for each target...
//
//      Retrieving environment variables from the default target:
//        defaultEnvVar: dft
//        processEnvVar: process
//        userEnvVar: user
//        machineEnvVar: (none)
//
//      Retrieving environment variables from the Process target:
//        defaultEnvVar: dft
//        processEnvVar: process
//        userEnvVar: user
//        machineEnvVar: (none)
//
//      Retrieving environment variables from the User target:
//        defaultEnvVar: (none)
//        processEnvVar: (none)
//        userEnvVar: user
//        machineEnvVar: (none)
//
//      Retrieving environment variables from the Machine target:
//        defaultEnvVar: (none)
//        processEnvVar: (none)
//        userEnvVar: (none)
//        machineEnvVar: machine
//
//      Deleting environment variables for each target...
//
// The example displays the following output if run on a Unix-based system:
//
//      Setting environment variables for each target...
//
//      Retrieving environment variables from the default target:
//        defaultEnvVar: dft
//        processEnvVar: process
//        userEnvVar: (none)
//        machineEnvVar: (none)
//
//      Retrieving environment variables from the Process target:
//        defaultEnvVar: dft
//        processEnvVar: process
//        userEnvVar: (none)
//        machineEnvVar: (none)
//
//      Retrieving environment variables from the User target:
//        defaultEnvVar: (none)
//        processEnvVar: (none)
//        userEnvVar: (none)
//        machineEnvVar: (none)
//
//      Retrieving environment variables from the Machine target:
//        defaultEnvVar: (none)
//        processEnvVar: (none)
//        userEnvVar: (none)
//        machineEnvVar: (none)
//
//      Deleting environment variables for each target...
module Sample

open System

// Environment variable names for default, process, user, and machine targets.
let rec defaultEnvVar = nameof defaultEnvVar
let rec processEnvVar = nameof processEnvVar
let rec userEnvVar = nameof userEnvVar
let rec machineEnvVar = nameof machineEnvVar

let rec dft = nameof dft
let rec proc = nameof proc
let rec user = nameof user
let rec machine = nameof machine

// Set the environment variable for each target.
printfn "Setting environment variables for each target...\n"
// The default target (the current process).
Environment.SetEnvironmentVariable(defaultEnvVar, dft)
// The current process.
Environment.SetEnvironmentVariable(processEnvVar, proc, EnvironmentVariableTarget.Process)
// The current user.
Environment.SetEnvironmentVariable(userEnvVar, user, EnvironmentVariableTarget.User)
// The local machine.
Environment.SetEnvironmentVariable(machineEnvVar, machine, EnvironmentVariableTarget.Machine)

// Define a list of environment variables.
let envVars = [ defaultEnvVar; processEnvVar; userEnvVar; machineEnvVar ]

// Try to get the environment variables from each target.
// The default (no specified target).
printfn "Retrieving environment variables from the default target:"
for envVar in envVars do
    let value = 
        match Environment.GetEnvironmentVariable envVar with
        | null -> "(none)"
        | v -> v
    printfn $"   {envVar}: {value}"

// The process block.
printfn "\nRetrieving environment variables from the Process target:"
for envVar in envVars do
    let value = 
        match Environment.GetEnvironmentVariable(envVar, EnvironmentVariableTarget.Process) with
        | null -> "(none)"
        | v -> v
    printfn $"   {envVar}: {value}"

// The user block.
printfn "\nRetrieving environment variables from the User target:"
for envVar in envVars do
    let value = 
        match Environment.GetEnvironmentVariable(envVar, EnvironmentVariableTarget.User) with
        | null -> "(none)"
        | v -> v
    printfn $"   {envVar}: {value}"

// The machine block.
printfn "\nRetrieving environment variables from the Machine target:"
for envVar in envVars do
    let value = 
        match Environment.GetEnvironmentVariable(envVar, EnvironmentVariableTarget.Machine) with
        | null -> "(none)"
        | v -> v
    printfn $"   {envVar}: {value}"

// Delete the environment variable for each target.
printfn "\nDeleting environment variables for each target...\n"
// The default target (the current process).
Environment.SetEnvironmentVariable(defaultEnvVar, null)
// The current process.
Environment.SetEnvironmentVariable(processEnvVar, null, EnvironmentVariableTarget.Process)
// The current user.
Environment.SetEnvironmentVariable(userEnvVar, null, EnvironmentVariableTarget.User)
// The local machine.
Environment.SetEnvironmentVariable(machineEnvVar, null, EnvironmentVariableTarget.Machine)

// The example displays the following output if run on a Windows system:
//      Setting environment variables for each target...
//
//      Retrieving environment variables from the default target:
//        defaultEnvVar: dft
//        processEnvVar: process
//        userEnvVar: user
//        machineEnvVar: (none)
//
//      Retrieving environment variables from the Process target:
//        defaultEnvVar: dft
//        processEnvVar: process
//        userEnvVar: user
//        machineEnvVar: (none)
//
//      Retrieving environment variables from the User target:
//        defaultEnvVar: (none)
//        processEnvVar: (none)
//        userEnvVar: user
//        machineEnvVar: (none)
//
//      Retrieving environment variables from the Machine target:
//        defaultEnvVar: (none)
//        processEnvVar: (none)
//        userEnvVar: (none)
//        machineEnvVar: machine
//
//      Deleting environment variables for each target...
//
// The example displays the following output if run on a Unix-based system:
//
//      Setting environment variables for each target...
//
//      Retrieving environment variables from the default target:
//        defaultEnvVar: dft
//        processEnvVar: process
//        userEnvVar: (none)
//        machineEnvVar: (none)
//
//      Retrieving environment variables from the Process target:
//        defaultEnvVar: dft
//        processEnvVar: process
//        userEnvVar: (none)
//        machineEnvVar: (none)
//
//      Retrieving environment variables from the User target:
//        defaultEnvVar: (none)
//        processEnvVar: (none)
//        userEnvVar: (none)
//        machineEnvVar: (none)
//
//      Retrieving environment variables from the Machine target:
//        defaultEnvVar: (none)
//        processEnvVar: (none)
//        userEnvVar: (none)
//        machineEnvVar: (none)
//
//      Deleting environment variables for each target...
Imports System.Collections
Imports Microsoft.Win32

Module Sample 
    Public Sub Main() 
        ' Environment variable names for default, process, user, and machine targets.
        Dim defaultEnvVar As String = NameOf(defaultEnvVar)
        Dim processEnvVar As String = NameOf(processEnvVar)
        Dim userEnvVar As String = NameOf(userEnvVar)
        Dim machineEnvVar As String = NameOf(machineEnvVar)

        Dim dft As String = NameOf(dft)
        Dim process As String = NameOf(process)
        Dim user As String = NameOf(user)
        Dim machine As String = NameOf(machine)

        ' Set the environment variable for each target.
        Console.WriteLine("Setting environment variables for each target...")
        ' The default target (the current process).
        Environment.SetEnvironmentVariable(defaultEnvVar, dft)
        ' The current process.
        Environment.SetEnvironmentVariable(processEnvVar, process, 
                                           EnvironmentVariableTarget.Process)
        ' The current user.
        Environment.SetEnvironmentVariable(userEnvVar, user, 
                                           EnvironmentVariableTarget.User)
        ' The local machine.
        Environment.SetEnvironmentVariable(machineEnvVar, machine, 
                                           EnvironmentVariableTarget.Machine)
        Console.WriteLine()

        ' Define an array of environment variables.
        Dim envVars As String() = { defaultEnvVar, processEnvVar, userEnvVar, machineEnvVar }
        
        ' Try to get the environment variables from each target.
        ' The default (no specified target).
        Console.WriteLine("Retrieving environment variables from the default target:")
        For Each envVar in envVars
          Dim value = Environment.GetEnvironmentVariable(envVar)
          Console.WriteLine($"   {envVar}: {If(value IsNot Nothing, value, "(none)")}")
        Next
        Console.WriteLine()
        ' The process block.
        Console.WriteLine("Retrieving environment variables from the Process target:")
        For Each envVar in envVars
          Dim value = Environment.GetEnvironmentVariable(envVar, EnvironmentVariableTarget.Process)
          Console.WriteLine($"   {envVar}: {If(value IsNot Nothing, value, "(none)")}")
        Next
        Console.WriteLine()
        ' The user block.
        Console.WriteLine("Retrieving environment variables from the User target:")
        For Each envVar in envVars
          Dim value = Environment.GetEnvironmentVariable(envVar, EnvironmentVariableTarget.User)
          Console.WriteLine($"   {envVar}: {value}")
        Next
        Console.WriteLine()
        ' The machine block.
        Console.WriteLine("Retrieving environment variables from the Machine target:")
        For Each envVar in envVars
          Dim value = Environment.GetEnvironmentVariable(envVar, EnvironmentVariableTarget.Machine)
          Console.WriteLine($"   {envVar}: {value}")
        Next
        Console.WriteLine()

        ' Delete the environment variable for each target.
        Console.WriteLine("Deleting environment variables for each target...")
        ' The default target (the current process).
        Environment.SetEnvironmentVariable(defaultEnvVar, Nothing)
        ' The current process.
        Environment.SetEnvironmentVariable(processEnvVar, Nothing, 
                                           EnvironmentVariableTarget.Process)
        ' The current user.
        Environment.SetEnvironmentVariable(userEnvVar, Nothing, 
                                           EnvironmentVariableTarget.User)
        ' The local machine.
        Environment.SetEnvironmentVariable(machineEnvVar, Nothing, 
                                           EnvironmentVariableTarget.Machine)
    End Sub
End Module
' The example displays the following output if run on a Windows system:
'      Setting environment variables for each target...
'
'      Retrieving environment variables from the default target:
'        defaultEnvVar: dft
'        processEnvVar: process
'        userEnvVar: user
'        machineEnvVar: (none)
'
'      Retrieving environment variables from the Process target:
'        defaultEnvVar: dft
'        processEnvVar: process
'        userEnvVar: user
'        machineEnvVar: (none)
'
'      Retrieving environment variables from the User target:
'        defaultEnvVar: (none)
'        processEnvVar: (none)
'        userEnvVar: user
'        machineEnvVar: (none)
'
'      Retrieving environment variables from the Machine target:
'        defaultEnvVar: (none)
'        processEnvVar: (none)
'        userEnvVar: (none)
'        machineEnvVar: machine
'
'      Deleting environment variables for each target...
'
' The example displays the following output if run on a Unix-based system:
'
'      Setting environment variables for each target...
'
'      Retrieving environment variables from the default target:
'        defaultEnvVar: dft
'        processEnvVar: process
'        userEnvVar: (none)
'        machineEnvVar: (none)
'
'      Retrieving environment variables from the Process target:
'        defaultEnvVar: dft
'        processEnvVar: process
'        userEnvVar: (none)
'        machineEnvVar: (none)
'
'      Retrieving environment variables from the User target:
'        defaultEnvVar: (none)
'        processEnvVar: (none)
'        userEnvVar: (none)
'        machineEnvVar: (none)
'
'      Retrieving environment variables from the Machine target:
'        defaultEnvVar: (none)
'        processEnvVar: (none)
'        userEnvVar: (none)
'        machineEnvVar: (none)
'
'      Deleting environment variables for each target...

Commenti

I nomi e i valori delle variabili di ambiente vengono archiviati come coppie chiave/valore nell'oggetto restituito IDictionary .

Nei sistemi Windows

Nei sistemi Windows il target parametro specifica se l'origine è il processo corrente, la chiave del Registro di sistema per l'utente corrente o la chiave del Registro di sistema per il computer locale.

Nei sistemi unix

Nei sistemi unix-like è supportato solo un target valore di EnvironmentVariableTarget.Process . Le variabili di ambiente per processo vengono ereditate dal processo padre (in genere la shell) usata per avviare il dotnet processo o sono definite nell'ambito del dotnet processo stesso. Al termine del processo dotnet, queste ultime variabili di ambiente non esistono.

Le variabili di ambiente per computer e per utente non sono supportate. Valore target di EnvironmentVariableTarget.Machine o EnvironmentVariableTarget.User restituisce una matrice vuota.

Nota

Nei sistemi Unix, le modifiche dell'ambiente in-process apportate dalle librerie native non vengono visualizzate dai chiamanti gestiti.

Vedi anche

Si applica a