C# Signature:

[DllImport("user32.dll")]
public static extern int EnumDisplaySettings (
      string deviceName, int modeNum, ref DEVMODE devMode );  

User-Defined Types:

DEVMODE

VB Signature:

<DllImport("user32", CharSet:=CharSet.Ansi, SetLastError:=True, ExactSpelling:=True)> _
Public Function EnumDisplaySettings(ByVal deviceName As String, ByVal modeNum As Integer, ByRef devMode As DEVMODE) As Integer
End Function

Notes:

You might want to:

const int ENUM_CURRENT_SETTINGS = -1;

const int ENUM_REGISTRY_SETTINGS = -2;

(This is my first pinvoke.net contribution and I'm new to C#. If you know what you're doing, please make sure I didn't major FAIL and remove this note).

Tips & Tricks:

Please add some!

Sample Code:

http://www.codeproject.com/csharp/CSDynamicScrRes.asp?df=100&forumid=38736&select=800137

or

using System.Runtime.InteropServices;

//insert by Zswang(wjhu111#21cn.com) at 2007-06-01

[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;

}

[DllImport("user32.dll")]

public static extern bool EnumDisplaySettings(string lpszDeviceName,

    int iModeNum, ref DEVMODE lpDevMode);

private void button1_Click(object sender, EventArgs e)

{

    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++;
    }

}

Alternative Managed API:

Do you know one? Please contribute it!