/// <summary>
/// Retrieve a new object of type T, whose properties and fields are
/// populated from an instance of the named WMI class. If the CIM
/// query results in multiple instances, only the first instance is
/// returned.
/// </summary>
/// <typeparam name="T">
/// The type of the object to be created. Must be a default-constructable
/// reference type.
/// </typeparam>
/// <param name="session">
/// The CIM session to be queried.
/// </param>
/// <param name="nameSpace">
/// A string containing the namespace to run the query against
/// </param>
/// <param name="wmiClassName">
/// A string containing the name of the WMI class from which to populate
/// the resultant object.
/// </param>
/// <returns>
/// A new object of type T if successful, null otherwise.
/// </returns>
/// <remarks>
/// This method matches property and field names of type T with identically
/// named properties in the WMI class instance. The WMI property is converted
/// to the type of T's property or field.
/// </remarks>
internal static T GetFirst <T>(CimSession session, string nameSpace, string wmiClassName) where T : class, new()
{
if (string.IsNullOrEmpty(wmiClassName))
{
throw new ArgumentException("String argument may not be null or empty", "wmiClassName");
}
try
{
var type = typeof(T);
var binding = BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance;
T rv = new T();
using (var instance = session.QueryFirstInstance(nameSpace, CIMHelper.WqlQueryAll(wmiClassName)))
{
SetObjectDataMembers(rv, binding, instance);
}
return(rv);
}
catch (Exception /*ex*/)
{
// on any error fall through to the null return below
}
return(null);
}
/// <summary>
/// Execute a CIM query and return only the first instance in the result.
/// </summary>
/// <param name="session">The CimSession to be queried</param>
/// <param name="query">A string containing the query to be run</param>
/// <returns>
/// A <see cref="Microsoft.Management.Infrastructure.CimInstance"/> object
/// representing the first instance in a query result if successful, null
/// otherwise.
/// </returns>
internal static CimInstance QueryFirstInstance(this CimSession session, string query)
{
return(session.QueryFirstInstance(CIMHelper.DefaultNamespace, query));
}
