/// <summary>
/// Convenient static helper method on RegistryKeyWrapper, for when someone is only intersted in knowing
/// whether a particular registry key exists or not.
/// </summary>
public static bool KeyExists(string registryKeyPath, RegistryHive registryHive, RegistryView registryView)
{
using (RegistryKeyWrapper wrapper = new RegistryKeyWrapper(registryKeyPath, registryHive, registryView))
{
return(wrapper.Exists());
}
}
/// <summary>
/// Returns the RegistryKeyWrapper around the sub key with name "name". If that does
/// not exist, returns a RegistryKeyWrapper around null.
/// </summary>
/// <param name="name"></param>
/// <returns></returns>
public virtual RegistryKeyWrapper OpenSubKey(string name)
{
ErrorUtilities.VerifyThrowArgumentLength(name, "name");
RegistryKeyWrapper wrapper = this;
string[] keyNames = name.Split(MSBuildConstants.BackslashChar, StringSplitOptions.RemoveEmptyEntries);
for (int i = 0; i < keyNames.Length && wrapper.Exists(); ++i)
{
try
{
wrapper = new RegistryKeyWrapper(wrapper.WrappedKey.OpenSubKey(keyNames[i], false /* not writeable */), _registryHive);
}
catch (Exception ex)
{
if (ExceptionHandling.NotExpectedRegistryException(ex))
{
throw;
}
throw new RegistryException(ex.Message, wrapper.Name + "\\" + keyNames[i], ex);
}
}
return(wrapper);
}
/// <summary>
/// Reads a string value from the specified registry key
/// </summary>
/// <param name="wrapper">wrapper around key</param>
/// <param name="valueName">name of the value</param>
/// <returns>string data in the value</returns>
private static string GetValue(RegistryKeyWrapper wrapper, string valueName)
{
if (wrapper.Exists())
{
object result = wrapper.GetValue(valueName);
// RegistryKey.GetValue returns null if the value is not present
// and String.Empty if the value is present and no data is defined.
// We preserve this distinction, because a string property in the registry with
// no value really has an empty string for a value (which is a valid property value)
// rather than null for a value (which is an invalid property value)
if (result != null)
{
// Must be a value of string type
if (!(result is string))
{
InvalidToolsetDefinitionException.Throw("NonStringDataInRegistry", wrapper.Name + "@" + valueName);
}
return(result.ToString());
}
}
return(null);
}