Here’s some code to programmatically find out if your laptop is currently running on battery power. I have created a Windows Form application and added the following code on a button click event which uses the SystemInformation.PowerStatus property

C#

private void btnPower_Click(object sender, EventArgs e)
{
   PowerLineStatus status = SystemInformation.PowerStatus.PowerLineStatus;
    if (status == PowerLineStatus.Offline)
        MessageBox.Show("Running on Battery");
    else
        MessageBox.Show("Running on Power");


}

VB.NET (Converted Code)

Private Sub btnPower_Click(ByVal sender As Object, ByVal e As EventArgs)
 Dim st As PowerLineStatus = SystemInformation.PowerStatus.PowerLineStatus
 If st = PowerLineStatus.Offline Then
     MessageBox.Show("Running on Battery")
 Else
     MessageBox.Show("Running on Power")
 End If

End Sub