RegistryKey.GetValue Method (String)

 

Retrieves the value associated with the specified name. Returns null if the name/value pair does not exist in the registry.

Namespace:   Microsoft.Win32
Assembly:  mscorlib (in mscorlib.dll)

Public Function GetValue (
	name As String
) As Object

Parameters

name
Type: System.String

The name of the value to retrieve. This string is not case-sensitive.

Return Value

Type: System.Object

The value associated with name, or null if name is not found.

Exception Condition
SecurityException

The user does not have the permissions required to read from the registry key.

ObjectDisposedException

The RegistryKey that contains the specified value is closed (closed keys cannot be accessed).

IOException

The RegistryKey that contains the specified value has been marked for deletion.

UnauthorizedAccessException

The user does not have the necessary registry rights.

System_CAPS_noteNote

A registry key can have one value that is not associated with any name. When this unnamed value is displayed in the registry editor, the string "(Default)" appears instead of a name. To retrieve this unnamed value, specify either null or the empty string ("") for name.

When the GetValue method retrieves expandable string values (RegistryValueKind.ExpandString), it expands environment strings using data from the local environment. To retrieve expandable string values from the registry on a remote computer, use the GetValue(String, Object, RegistryValueOptions) method overload to specify that you do not want environment strings expanded.

System_CAPS_noteNote

If a value containing expandable references to environment variables has been stored as a string (RegistryValueKind.String), rather than as an expandable string (RegistryValueKind.ExpandString), GetValue does not expand it. You can expand such a string after it has been retrieved by calling the ExpandEnvironmentVariables method.

System_CAPS_noteNote

The recommended way to retrieve data from the PerformanceData key is to use the PerformanceCounter class rather than the RegistryKey.GetValue method.

GetValue does not support reading values of type REG_NONE or REG_LINK. In both cases, the default value (null) is returned instead of the actual value.

The following code example creates a test key and adds values of different data types to the key. The example then reads the name/value pairs and displays them to the console, using the GetValueKind method to retrieve the corresponding registry data types.

Imports System
Imports Microsoft.Win32
Imports Microsoft.VisualBasic

Public Class Example
    Public Shared Sub Main()
        ' Delete and recreate the test key.
        Registry.CurrentUser.DeleteSubKey("RegistryValueKindExample", False)
        Dim rk As RegistryKey = Registry.CurrentUser.CreateSubKey("RegistryValueKindExample")

        ' Create name/value pairs.
        ' This overload supports QWord (long) values. 
        rk.SetValue("QuadWordValue", 42, RegistryValueKind.QWord)

        ' The following SetValue calls have the same effect as using the
        ' SetValue overload that does not specify RegistryValueKind.
        '
        rk.SetValue("DWordValue", 42, RegistryValueKind.DWord)
        rk.SetValue("MultipleStringValue", New String() {"One", "Two", "Three"}, RegistryValueKind.MultiString)
        rk.SetValue("BinaryValue", New Byte() {10, 43, 44, 45, 14, 255}, RegistryValueKind.Binary)
        rk.SetValue("StringValue", "The path is %PATH%", RegistryValueKind.String) 

        ' This overload supports setting expandable string values. Compare
        ' the output from this value with the previous string value.
        rk.SetValue("ExpandedStringValue", "The path is %PATH%", RegistryValueKind.ExpandString)


        ' Display all name/value pairs stored in the test key, with each
        ' registry data type in parentheses.
        '
        Dim valueNames As String() = rk.GetValueNames()
        Dim s As String
        For Each s In  valueNames
            Dim rvk As RegistryValueKind = rk.GetValueKind(s)
            Select Case rvk
                Case RegistryValueKind.MultiString
                    Dim values As String() = CType(rk.GetValue(s), String())
                    Console.Write(vbCrLf & " {0} ({1}) =", s, rvk)
                    For i As Integer = 0 To values.Length - 1
                        If i <> 0 Then Console.Write(",")
                        Console.Write(" ""{0}""", values(i))
                    Next i
                    Console.WriteLine()

                Case RegistryValueKind.Binary
                    Dim bytes As Byte() = CType(rk.GetValue(s), Byte())
                    Console.Write(vbCrLf & " {0} ({1}) =", s, rvk)
                    For i As Integer = 0 To bytes.Length - 1
                        ' Display each byte as two hexadecimal digits.
                        Console.Write(" {0:X2}", bytes(i))
                    Next i
                    Console.WriteLine()

                Case Else
                    Console.WriteLine(vbCrLf & " {0} ({1}) = {2}", s, rvk, rk.GetValue(s))
            End Select
        Next s
    End Sub 'Main
End Class 'Example

'
'This code example produces the following output (some output is omitted):
'
' QuadWordValue (QWord) = 42
'
' DWordValue (DWord) = 42
'
' MultipleStringValue (MultiString) = "One", "Two", "Three"
'
' BinaryValue (Binary) = 0A 2B 2C 2D 0E FF
'
' StringValue (String) = The path is %PATH%
'
' ExpandedStringValue (ExpandString) = The path is C:\Program Files\Microsoft.NET\SDK\v2.0\Bin;
' [***The remainder of this output is omitted.***]

RegistryPermission

to read from the registry. Associated enumeration: RegistryPermissionAccess.Read

EnvironmentPermission

to read a registry key of type REG_EXPAND_SZ. Associated enumeration: PermissionState.Unrestricted

.NET Framework
Available since 1.1
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