[ask] detect all computer in network

[paul_heru]

hello,
can anybody teach me how to do that(I'm newbie in network programming), to detect all the computer name's list in the network(LAN with(out) domain) and also the IP's list of the computers, thanks before

[gigemboy]

Well.. theres lots of ways I would imagine.. but we need an idea of your network... do you use Active Directory? Is this being ran on a server or on a client machine?

[paul_heru]

maybe from just the basic LAN, just simple networking without the server, so the program just detecting all the comp in LAN

[gigemboy]

I couldnt find any info on the subject when searching around. Looks like you might have to resort to api...

I did find this one link of a VB6 project that uses a couple classes in order to list the computers in a domain using API, of course it would need to be converted to .NET code..
http://www.planet-source-code.com/vb...15174&lngWId=1

[paul_heru]

well, thanks for the effort to help me, i'll try to look at it then

[dee-u]

Perhaps you could also utilize the output of Net View or use WMI...

[paul_heru]

Perhaps you could also utilize the output of Net View or use WMI...

what is Net View and WMI, and how could I use that for detecting comps in network ?

[RobDog888]

You would need to write some unmanaged code suing the NetServerEnum API. I have some code that does it but its in VB6. I havent converted it to VB.NET yet as I havent had the need. Maybe if no one else has a solution I will make an effort to convert it.

[dee-u]

You would need to write some unmanaged code suing the NetServerEnum API. I have some code that does it but its in VB6. I havent converted it to VB.NET yet as I havent had the need. Maybe if no one else has a solution I will make an effort to convert it.

Go Rob!

[RobDog888]

Well, basically I'm waiting for John to post stating that it can be done easily with a certain class in .NET. I think I'll search until then. Maybe I'll beat him to it.

[RobDog888]

so far I found a calss to determine if your local system is connected to a network or not.

MessageBox.Show(System.Windows.Forms.SystemInformation.Network.ToString())

[RobDog888]

Guess I'll have a go at it then.

What is "LMCSTR"? Its in an API declaration.

[RobDog888]

I think its something like this?

<MarshalAs(UnmanagedType.LPStr)> _
Private Const LMCSTR As Int32 = LPCSTR
<MarshalAs(UnmanagedType.LPStr)> _
Private Const LPCSTR As Int32 = UnmanagedType.LPStr

[paul_heru]

????
sorry but im really2 confused

[RobDog888]

I am about 75% way complete but I have run into a couple of issues converting the calls. I dont think I will be done tonight. Should be able to post it tomorrow.

[gigemboy]

Gotta love those API call conversions... (remember.. byval or byref )

[RobDog888]

Hey gig! Mind if I throw some APIs at you?

<StructLayout(LayoutKind.Sequential)> _
    Public Structure SERVER_INFO_100
        <MarshalAs(UnmanagedType.LPStr)> _
        Friend sv100_platform_id As Integer
        <MarshalAs(UnmanagedType.LPStr)> _
        Friend sv100_name As Integer
    End Structure
 
    Private Declare Auto Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (ByVal pTo As Integer, ByRef uFrom As Integer, ByVal lSize As Integer)
    Private Declare Auto Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (ByVal pTo As String, ByRef uFrom As Integer, ByVal lSize As Integer)
 
Private Sub Button1_Click(blah, blah, blah....
    Dim se100 As SERVER_INFO_100
    Dim bufptr As Integer
    Dim nStructSize As Integer
    Dim Cnt As Integer
 
    '...
 
    CopyMemory(se100, bufptr + (nStructSize * Cnt), nStructSize) 'ERROR

Error is

D:\Development\Tips .NET\Network Neighborhood\clsNetwork.vb(61): Overload resolution failed because no accessible 'CopyMemory' can be called with these arguments:
'Declare Auto Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (pTo As String, ByRef uFrom As Integer, lSize As Integer)': Value of type 'Network_Neighborhood.clsNetwork.SERVER_INFO_100' cannot be converted to 'String'.
'Declare Auto Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (pTo As Integer, ByRef uFrom As Integer, lSize As Integer)': Value of type 'Network_Neighborhood.clsNetwork.SERVER_INFO_100' cannot be converted to 'Integer'.

[gigemboy]

First instinct would be to change "ByRef uFrom" to "ByVal uFrom" ... (it worked before hehehe)... but id have to search for examples of that, because ive never used it before..

[RobDog888]

I think that part is ok but the error message shows that its the conversion of the structure to a string or integer.

SERVER_INFO_100' cannot be converted to 'String'
SERVER_INFO_100' cannot be converted to 'Integer'

I overloaded the API call to see if either would work but nada.

[gigemboy]

Hey rob.. check out this link... has sample of vb.net code using it.. lists the declaration they use as well as their server_info_100 structure

http://www.eggheadcafe.com/forums/Fo...11135&INTID=14

***EDIT -Whoops.. forgot its the copymemory that the problem is at....

[RobDog888]

Cool! I dont like the way they do it but I will use the types for the APIs. I was sooo close. Intptr intstead of Integer. Shouldnt be long now.

Also, Marshal.SizeOf instead of LenB

[RobDog888]

Looks like they dont even use CopyMemory. The use a DirectCast -

se101 = DirectCast(Marshal.PtrToStructure(New IntPtr(bufptr.ToInt32 + (nStructSize * cnt)), GetType(SERVER_INFO_101)), SERVER_INFO_101)

[RobDog888]

I got the class file to work now. Its similar to the link gig posted. I'll attach it if you want. I think I will make a little Net Neighborhood program out of it just for fun.

[paul_heru]

I got the class file to work now. Its similar to the link gig posted. I'll attach it if you want. I think I will make a little Net Neighborhood program out of it just for fun.

thanks rob , but how to use it?, ill be waiting for your source code of the program

[dee-u]

How about this?

[jo0ls]

for the without domain bit:
from google groups

'
    'Imports system.runtime.interopservices
    Dim WithEvents b As New Button
    Dim lv As New ListView
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        b.Location = New Point((Me.ClientSize.Width - b.Width) \ 2, Me.ClientSize.Height - 60)
        b.Text = "list"
        lv.View = View.Details
        lv.Columns.Add("Workgroup Computers", 300, HorizontalAlignment.Left)
        lv.Dock = DockStyle.Top
        lv.Height = Me.ClientSize.Height - 80
        Me.Controls.Add(lv)
        Me.Controls.Add(b)
        AddHandler b.Click, AddressOf b_click
    End Sub
 
    Declare Unicode Function NetServerEnum Lib "Netapi32.dll" _
    (ByVal Servername As Integer, ByVal level As Integer, _
        ByRef buffer As Integer, ByVal PrefMaxLen As Integer, _
        ByRef EntriesRead As Integer, ByRef TotalEntries As Integer, _
        ByVal ServerType As Integer, ByVal DomainName As String, _
        ByRef ResumeHandle As Integer) As Integer
 
    Declare Function NetApiBufferFree Lib "Netapi32.dll" _
        (ByVal lpBuffer As Integer) As Integer
 
 
    Structure Computer_info_101
        Public Platform_ID As Integer
        <MarshalAsAttribute(UnmanagedType.LPWStr)> Public Name As String
        Public Version_Major As Integer
        Public Version_Minor As Integer
        Public Type As Integer
        <MarshalAsAttribute(UnmanagedType.LPWStr)> Public Comment As String
    End Structure
 
    Private Const SV_TYPE_SERVER As Integer = &H2 ' All Servers
 
    Private Sub ListCompsInWorkgroup()
 
        Dim ComputerInfo As Computer_info_101
        Dim i, MaxLenPref, level, ret, EntriesRead, TotalEntries, ResumeHandle As Integer
        Dim BufPtr As Integer
        Dim iPtr As IntPtr
        MaxLenPref = -1
        level = 101
        ret = NetServerEnum(0, level, BufPtr, MaxLenPref, EntriesRead, TotalEntries, _
        SV_TYPE_SERVER, "MSHOME", ResumeHandle) ' Enter your workgroup name here
        If ret <> 0 Then
            Console.WriteLine("An Error has occured")
            Return
        End If
        ' loop thru the entries
        For i = 0 To EntriesRead - 1
            ' copy the stuff into our structure
            Dim ptr As IntPtr = New IntPtr(BufPtr)
            ComputerInfo = CType(Marshal.PtrToStructure(ptr, GetType(Computer_info_101)), _
            Computer_info_101)
            BufPtr = BufPtr + Len(ComputerInfo)
            lv.Items.Add(ComputerInfo.Name)
        Next
        NetApiBufferFree(BufPtr)
 
    End Sub
 
    Private Sub b_click(ByVal sender As Object, ByVal e As System.EventArgs)
        ListCompsInWorkgroup()
    End Sub

[RobDog888]

I posted the source code in the class attachment. Just use it like so.

'Adds to a listview control:
 
        Dim Servers As New clsNetwork
        Dim compNames As New ArrayList
        Dim compName As String
        Dim x As Integer
 
        compNames = Servers.GetServers(vbNullString, Servers.SV_TYPE_ALL).Clone()
        For x = 0 To compNames.Count - 1
            lvwNetwork.Items.Add(compNames.Item(x).ToString)
        Next
        compNames.Clear()

[paul_heru]

thanks to all,
and i've tried rob's program(it worked), and jools too, thanks to u all, now i must learn the source code.

[paul_heru]

o , and what about the IP number of each computer, and in jools code, we must enter workgroup's name by ourself, but how to make the program automatically search comps name and ip only in its workgroup, thanks

[VBProgrammer1]

Heya, could you please give your version in VB6 Rob?

[saechira]

Can anyone let me know where ROb's class attachment exists so that I can try it out? I am in dire need of that? where can I find clsNetwork?