Get a User's Full Name

[DllImport("secur32.dll", CharSet = CharSet.Auto)]
public static extern int GetUserNameEx(int nameFormat, StringBuilder userName, ref int userNameSize);

private void Form1_Load(object sender, EventArgs e)
{
    label1.Text = GetUserDisplayName();
}

private static string GetUserDisplayName()
{
    string userName = Environment.UserName;
    if (Environment.OSVersion.Platform == PlatformID.Win32NT)
    {
        StringBuilder buffer = new StringBuilder(1024);
        int bufferSize = buffer.Capacity;
        int returnValue = GetUserNameEx((int)EXTENDED_NAME_FORMAT.NameDisplay, buffer, ref bufferSize);
        if (returnValue != 0)
        {
            // GetUserNameEx was successful
            userName = buffer.ToString();
        }
    }
    return userName;
}

enum EXTENDED_NAME_FORMAT
{
    NameUnknown = 0,
    NameFullyQualifiedDN = 1,
    NameSamCompatible = 2,
    NameDisplay = 3,
    NameUniqueId = 6,
    NameCanonical = 7,
    NameUserPrincipal = 8,
    NameCanonicalEx = 9,
    NameServicePrincipal = 10,
    NameDnsDomain = 12
}

Module User
    <DllImport("secur32.dll")> _
    Public Function GetUserNameEx(ByVal nameFormat As Integer, ByVal userName As StringBuilder, ByRef userNameSize As Integer) As Integer
    End Function

    Enum EXTENDED_NAME_FORMAT
        NameUnknown = 0
        NameFullyQualifiedDN = 1
        NameSamCompatible = 2
        NameDisplay = 3
        NameUniqueId = 6
        NameCanonical = 7
        NameUserPrincipal = 8
        NameCanonicalEx = 9
        NameServicePrincipal = 10
        NameDnsDomain = 12
    End Enum

    Function GetUserDisplayName() As String
        Dim userName As String = Environment.UserName
        If Environment.OSVersion.Platform = PlatformID.Win32NT Then
            Dim buffer As StringBuilder = New StringBuilder(1024)
            Dim bufferSize As Integer = buffer.Capacity
            Dim returnValue As Integer = GetUserNameEx(CInt(EXTENDED_NAME_FORMAT.NameDisplay), buffer, bufferSize)
            If returnValue <> 0 Then
                ' GetUserNameEx was successful            
                userName = buffer.ToString()
            End If
        End If
        Return userName
    End Function
End Module

BOOL CShowActiveDirUsers::GetFullUserName(LPTSTR szUser, LPTSTR szDomain, 
							LPTSTR szFullUserName, LPTSTR szDescription)
{
	BOOL	bResult = FALSE;
	LPWSTR	pServer = NULL;
	BOOL	bLocal = FALSE;
	TCHAR	szComputerName[_MAX_PATH];
	TCHAR   szDomainName[_MAX_PATH];
	TCHAR   szServer[_MAX_PATH];
	TCHAR   szPDC[_MAX_PATH];
	DWORD	dwLevel = 10;
	LPUSER_INFO_10 pUserInfoBuffer = NULL;

	// init
	ZeroMemory(szComputerName, _MAX_PATH);
	ZeroMemory(szDomainName, _MAX_PATH);
	ZeroMemory(szServer, _MAX_PATH);
	ZeroMemory(szPDC, _MAX_PATH);
	

	GetLocalComputerName(szComputerName);

	if (_tcsicmp(szComputerName, szDomain) == 0)
		bLocal = TRUE;

	// for active directory native, szUser comes in as user@domain.com
	if (!bLocal) 
	{
		GetDCName(szPDC, szDomain);
		if (_tcschr(szUser, AT) )
		{
			GetUserAndDomainNameFromUPN(szUser, szFullUserName, szDomainName);
			_tcscpy(szUser, szFullUserName);
			_tcscpy(szDomain, szDomainName);
		}
	}
	else
	{
		NetApiBufferAllocate(_MAX_PATH,  (LPVOID*)&pServer);
		ZeroMemory(pServer, _MAX_PATH);
		_tcscpy(pServer, DOUBLE_BACKSLASH);
		_tcscat(pServer, szComputerName);

	}

	// grab the details of the user account, 
	// may fail if AD=native & user not in proper security group
	if (NERR_Success == NetUserGetInfo(szPDC, szUser, dwLevel, 
											(LPBYTE*)&pUserInfoBuffer))
	{
		if (pUserInfoBuffer)
		{
			_tcscpy(szFullUserName, pUserInfoBuffer->usri10_full_name);
			_tcscpy(szDescription, pUserInfoBuffer->usri10_comment);
			bResult = TRUE;
		}
	}

	if (pUserInfoBuffer)
		NetApiBufferFree(pUserInfoBuffer);

	if (pServer)
		NetApiBufferFree(pServer);

	return bResult;
}

jabit wrote:

I didn't know people here would be opposed to posting a simple article on a particular feature of the framework.