If you mean video modes are available resolutions, try to invoke EnumDisplaySettingsEx
details can be found here:
http://msdn.microsoft.com/en-us/library/dd162612(VS.85).aspx
small program that lists available resolutions:
using System;
using System.Linq;
using System.Runtime.InteropServices;
using System.Windows.Forms;
namespace ListResolutions
{
class Program
{
[DllImport("user32.dll")]
public static extern bool EnumDisplaySettings(
string deviceName, int modeNum, ref DEVMODE devMode);
const int ENUM_CURRENT_SETTINGS = -1;
const int ENUM_REGISTRY_SETTINGS = -2;
[StructLayout(LayoutKind.Sequential)]
public struct DEVMODE
{
private const int CCHDEVICENAME = 0x20;
private const int CCHFORMNAME = 0x20;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 0x20)]
public string dmDeviceName;
public short dmSpecVersion;
public short dmDriverVersion;
public short dmSize;
public short dmDriverExtra;
public int dmFields;
public int dmPositionX;
public int dmPositionY;
public ScreenOrientation dmDisplayOrientation;
public int dmDisplayFixedOutput;
public short dmColor;
public short dmDuplex;
public short dmYResolution;
public short dmTTOption;
public short dmCollate;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 0x20)]
public string dmFormName;
public short dmLogPixels;
public int dmBitsPerPel;
public int dmPelsWidth;
public int dmPelsHeight;
public int dmDisplayFlags;
public int dmDisplayFrequency;
public int dmICMMethod;
public int dmICMIntent;
public int dmMediaType;
public int dmDitherType;
public int dmReserved1;
public int dmReserved2;
public int dmPanningWidth;
public int dmPanningHeight;
}
static void Main(string[] args)
{
DEVMODE vDevMode = new DEVMODE();
int i = 0;
while (EnumDisplaySettings(null, i, ref vDevMode))
{
Console.WriteLine("Width:{0} Height:{1} Color:{2} Frequency:{3}",
vDevMode.dmPelsWidth,
vDevMode.dmPelsHeight,
1 << vDevMode.dmBitsPerPel, vDevMode.dmDisplayFrequency
);
i++;
}
}
}
}