VB .NET and API

[ashrobo]

hi all, i've got the following code from MSDN but couldn't get it to work. :(

 

Declare Function GetUserName Lib "advapi32.dll" Alias "GetUserNameA" (ByVal lpBuffer As String, ByVal nSize As Integer) As Integer

 

Dim Ret As Integer

Dim UserName As String

Dim Buffer As String

Buffer = New String(CChar(" "), 25)

Ret = GetUserName(Buffer, 25)

UserName = Microsoft.VisualBasic.Left(Buffer, InStr(Buffer, Chr(0)) - 1)

MsgBox(UserName)

 

i added Microsoft.VisualBasic. because it wouldn't allow me to use Left

 

encountered the following error while trying to run it.

 

>> Ret = GetUserName(Buffer, 25) 'error occurs here

 

An unhandled exception of type 'System.NullReferenceException' occurred in WindowsApplication3.exe

 

Additional information: Object reference not set to an instance of an object.

 

has anyone encountered this before? all help will be appreciated!

 

-ashrobo

[quwiltw]

I'm not sure what the problem is but you can get the username from System.Environment.

[ashrobo]

i'm trying to get the domain that the user is logged on.

[quwiltw]

Did you even take a second to look at the System.Environment before responding?:-\

[ashrobo]

Did you even take a second to look at the System.Environment before responding?:-\

just in case you're wondering, yes i have. Environment.UserName gets me the username of the user that's logged on, Environment.UserDomainName gives me the machine name. i've tried them before asking of course.

[Guest mutant]

Not sure if it will work but try this:

System.Security.Principal.WindowsIdentity.GetCurrent.Name

[ashrobo]

System.Security.Principal.WindowsIdentity.GetCurrent() .Name works (it gives me the domain\username). guess i'll just have to use this.. thanks mutant! (=

[quwiltw]

System.Environment.UserDomainName() returns the network domain that you're currently logged on to just as the documentation says. Not sure why it would return the machine name in your case.

[ashrobo]

i have no idea why that happens about System.Environment.UserDomainName() but i found out why it is so with the SystemInformation.UserDomainName()

The name of the user domain. If a local user account exists with the same name as the user name, this property gets the computer name.

[subbu_vairavan]

Also if the user name and machine name are same, this property gets the computer name

[k_murali_k]

what if I want to findout user who logged in another system in the network?

 

Murali Krishna