Registry::SetValue Method


Sets the value of a name/value pair in a registry key.

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

System_CAPS_pubmethodSystem_CAPS_staticSetValue(String^, String^, Object^)

Sets the specified name/value pair on the specified registry key. If the specified key does not exist, it is created.

System_CAPS_pubmethodSystem_CAPS_staticSetValue(String^, String^, Object^, RegistryValueKind)

Sets the name/value pair on the specified registry key, using the specified registry data type. If the specified key does not exist, it is created.

The following code example stores values of several data types in an example key, creating the key as it does so, and then retrieves and displays the values. The example demonstrates storing and retrieving the default (nameless) name/value pair, and the use of defaultValue when a name/value pair does not exist.

using namespace System;
using namespace Microsoft::Win32;

int main()
    // The name of the key must include a valid root.
    String^ userRoot = "HKEY_CURRENT_USER";
    String^ subKey = "RegistrySetValueExample2";
    String^ keyName = String::Concat(userRoot, "\\", subKey);

    // An int value can be stored without specifying the
    // registry data type, but Int64 values will be stored
    // as strings unless you specify the type. Note that
    // the int is stored in the default name/value
    // pair.
    Registry::SetValue(keyName, "", 5280);
    Registry::SetValue(keyName, "TestInt64", 12345678901234, 

    // Strings with expandable environment variables are
    // stored as ordinary strings unless you specify the
    // data type.
    Registry::SetValue(keyName, "TestExpand", "My path: %path%");
    Registry::SetValue(keyName, "TestExpand2", "My path: %path%", 

    // Arrays of strings are stored automatically as 
    // MultiString. Similarly, arrays of Byte are stored
    // automatically as Binary.
    array<String^>^ strings  = {"One", "Two", "Three"};
    Registry::SetValue(keyName, "TestArray", strings);

    // Your default value is returned if the name/value pair
    // does not exist.
    String^ noSuch = (String^)Registry::GetValue(keyName, 
        "Return this default if NoSuchName does not exist.");
    Console::WriteLine("\r\nNoSuchName: {0}", noSuch);

    // Retrieve the int and Int64 values, specifying 
    // numeric default values in case the name/value pairs
    // do not exist. The int value is retrieved from the
    // default (nameless) name/value pair for the key.
    int testInteger = (int)Registry::GetValue(keyName, "", -1);
    Console::WriteLine("(Default): {0}", testInteger);
    long long testInt64 = (long long)Registry::GetValue(keyName, 
        "TestInt64", System::Int64::MinValue);
    Console::WriteLine("TestInt64: {0}", testInt64);

    // When retrieving a MultiString value, you can specify
    // an array for the default return value. 
    array<String^>^ testArray = (array<String^>^)Registry::GetValue(
        keyName, "TestArray", 
        gcnew array<String^> {"Default if TestArray does not exist."});
    for (int i = 0; i < testArray->Length; i++)
        Console::WriteLine("TestArray({0}): {1}", i, testArray[i]);

    // A string with embedded environment variables is not
    // expanded if it was stored as an ordinary string.
    String^ testExpand = (String^)Registry::GetValue(keyName, 
        "TestExpand", "Default if TestExpand does not exist.");
    Console::WriteLine("TestExpand: {0}", testExpand);

    // A string stored as ExpandString is expanded.
    String^ testExpand2 = (String^)Registry::GetValue(keyName, 
        "TestExpand2", "Default if TestExpand2 does not exist.");
        "TestExpand2: {0}...", testExpand2->Substring(0, 40));
        "\r\nUse the registry editor to examine the key.");
    Console::WriteLine("Press the Enter key to delete the key.");
// This code example produces output similar to the following:
// NoSuchName: Return this default if NoSuchName does not exist.
// (Default): 5280
// TestInt64: 12345678901234
// TestArray(0): One
// TestArray(1): Two
// TestArray(2): Three
// TestExpand: My path: %path%
// TestExpand2: My path: D:\Program Files\Microsoft.NET\...
// Use the registry editor to examine the key.
// Press the Enter key to delete the key.
Return to top