C# Signature:

[DllImport("coredll.dll")]
static extern bool GetSystemPowerStatusEx(SYSTEM_POWER_STATUS_EX pStatus,
   bool fUpdate);

VB .NET Signature:

Declare Function GetSystemPowerStatusEx Lib "coredll.dll" _
   (<Out()> ByRef pStatus As SYSTEM_POWER_STATUS_EX, _
   ByVal fUpdate As Boolean) As Boolean

User-Defined Types:

SYSTEM_POWER_STATUS_EX

Notes:

pStatus must be a valid object as values will be passed back in this structure. As pStatus itself is not changed do not use the ref/out keywords in C#.

Tips & Tricks:

Please add some!

Sample Code:

    public static byte GetBatteryLeftPercentage()
    {
        SYSTEM_POWER_STATUS_EX powerStatus = new SYSTEM_POWER_STATUS_EX();

        GetSystemPowerStatusEx(powerStatus, true);
        return powerStatus.BackupBatteryLifePercent;
    }

Alternative Managed API:

TODO