get the current Username

Author: Thomas Stutz

{1.}

function GetCurrentUserName: string;

const

cnMaxUserNameLen = 254;

var

sUserName: string;

dwUserNameLen: DWORD;

begin

dwUserNameLen := cnMaxUserNameLen - 1;

SetLength(sUserName, cnMaxUserNameLen);

GetUserName(PChar(sUserName), dwUserNameLen);

SetLength(sUserName, dwUserNameLen);

Result := sUserName;

end;

procedure TForm1.Button1Click(Sender: TObject);

begin

ShowMessage(GetCurrentUserName);

end;

{2.}

function GetCurrentUserName(var CurrentUserName: string): Boolean;

var

BufferSize: DWORD;

pUser: PChar;

begin

BufferSize := 0;

GetUserName(nil, BufferSize);

pUser := StrAlloc(BufferSize);

try

Result := GetUserName(pUser, BufferSize);

CurrentUserName := StrPas(pUser);

finally

StrDispose(pUser);

end;

end;

procedure TForm1.Button1Click(Sender: TObject);

var

CurrentUserName: string;

begin

GetCurrentUserName(CurrentUserName);

Label1.Caption := CurrentUserName;

end;

{*********************************************}

{

Windows NT/2000/XP:

The GetUserNameEx function retrieves the name of the user or other

security principal associated with the calling thread.

You can specify the format of the returned name.

If the thread is impersonating a client, GetUserNameEx

returns the name of the client.

}

const

NameUnknown = 0; // Unknown name type.

NameFullyQualifiedDN = 1; // Fully qualified distinguished name

NameSamCompatible = 2; // Windows NT® 4.0 account name

NameDisplay = 3; // A "friendly" display name

NameUniqueId = 6; // GUID string that the IIDFromString function returns

NameCanonical = 7; // Complete canonical name

NameUserPrincipal = 8; // User principal name

NameCanonicalEx = 9;

NameServicePrincipal = 10; // Generalized service principal name

DNSDomainName = 11; // DNS domain name, plus the user name

procedure GetUserNameEx(NameFormat: DWORD;

lpNameBuffer: LPSTR; nSize: PULONG); stdcall;

external 'secur32.dll' Name 'GetUserNameExA';

function LoggedOnUserNameEx(fFormat: DWORD): string;

var

UserName: array[0..250] of char;

Size: DWORD;

begin

Size := 250;

GetUserNameEx(fFormat, @UserName, @Size);

Result := UserName;

end;

procedure TForm1.Button1Click(Sender: TObject);

begin

Edit1.Text := LoggedOnUserNameEx(NameSamCompatible);

end;