Getting All Users In A Computer

Ibrahim Ersoy

8y34.7k70100Article

C#UsersNetwork Programming

7 Comments

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Riddhi Valecha10y ago
My post - www.c-sharpcorner.com/forums/resultpropertycollection-resultpropertyvaluecollection
Riddhi Valecha10y ago
Requirement is - I have to make an online application that shows the system status on continuous basis of all users, along with their details ...Just like in news channels, news keep flashing , I have to keep flashing the data on continuous basis of all users ... This will include everything - Last login date, manager name, email id, emp code, etc ... User/Domain Last Login Date Time Last Logout Date Time Manager Emp CodeAbc.xyz.com 1-jan-2016 1:1:1 2-jan-2016 3:3:3 Mahesh Bhatt 12345 User Properties - Emp Code, email, manager name, email , department, location, company joining date, company leaving date(if applicable), etc
Riddhi Valecha10y ago
I have one more requirement ...Can you please guide me...
Riddhi Valecha10y ago
Hi... Thanks a ton.. this code really helped...
Ibrahim Ersoy14y ago
Thank you! You can get only logged-in username with Environment,using Network APIs you can get all of them whether they logged in or not.
Mahesh Chand14y ago
How about Environment class? http://msdn.microsoft.com/en-us/library/system.environment.aspx I thought it had member for the same so we don't need to call WinAPI
Mahesh Chand14y ago
You're on a roll!

First we'll create a class to process WinApi calls.

This Class has been written by Michael Bright in 2003.Since then i've been using this code and extending it for network related needs.

using System;
using System.Runtime.InteropServices;
namespace GettingAllUsers {
public class NetworkAPI {
// USER_INFO_1 - Strucutre to hold obtained user information
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct USER_INFO_1 {
public string usri1_name;
public string usri1_password;
public int usri1_password_age;
public int usri1_priv;
public string usri1_home_dir;
public string comment;
public int usri1_flags;
public string usri1_script_path;
}
// USER_INFO_0 - Structure to hold Just Usernames
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct USER_INFO_0 {
public String Username;
}
// NetUserAdd - To Add Users to a local machine or Network
[DllImport("Netapi32.dll")]
public extern static int NetUserAdd([MarshalAs(UnmanagedType.LPWStr)] string servername, int level, ref USER_INFO_1 buf, int parm_err);
// NetUserDel - To delete Users from a local machine or Network
[DllImport("Netapi32.dll")]
public extern static int NetUserDel([MarshalAs(UnmanagedType.LPWStr)] string servername, [MarshalAs(UnmanagedType.LPWStr)] string username);
// NetUserGetInfo - Returns to a struct Information about the specified user
[DllImport("Netapi32.dll")]
public extern static int NetUserGetInfo([MarshalAs(UnmanagedType.LPWStr)] string servername, [MarshalAs(UnmanagedType.LPWStr)] string username, int level, out IntPtr bufptr);
// NetUserSetInfo - Allows us to modify User information
[DllImport("Netapi32.dll")]
public extern static int NetUserSetInfo([MarshalAs(UnmanagedType.LPWStr)] string servername, [MarshalAs(UnmanagedType.LPWStr)] string username, int level, ref USER_INFO_1 buf, int error);
// NetUserChangePassword - Allows us to change a users password providing we have it
[DllImport("Netapi32.dll")]
public extern static int NetUserChangePassword([MarshalAs(UnmanagedType.LPWStr)] string domainname, [MarshalAs(UnmanagedType.LPWStr)] string username, [MarshalAs(UnmanagedType.LPWStr)] string oldpassword, [MarshalAs(UnmanagedType.LPWStr)] string newpassword);
// NetUserEnum - Obtains a list of all users on local machine or network
[DllImport("Netapi32.dll")]
public extern static int NetUserEnum(string servername, int level, int filter, out IntPtr bufptr, int prefmaxlen, out int entriesread, out int totalentries, out int resume_handle);
// NetAPIBufferFree - Used to clear the Network buffer after NetUserEnum
[DllImport("Netapi32.dll")]
public extern static int NetApiBufferFree(IntPtr Buffer);
public NetworkAPI() {
//
// TODO: Add constructor logic here
//
}
}
}

Add a ListBox in your form and then,Later inside your main application create a function:

public void EnumerateUsers() {
int EntriesRead;
int TotalEntries;
int Resume;
listBox1.Items.Clear();
IntPtr bufPtr;
NetworkAPI.NetUserEnum(null, 0, 2, out bufPtr, -1, out EntriesRead, out TotalEntries, out Resume);
if (EntriesRead > 0) {
NetworkAPI.USER_INFO_0[] Users = new NetworkAPI.USER_INFO_0[EntriesRead];
IntPtr iter = bufPtr;
for (int i = 0; i < EntriesRead; i++) {
Users[i] = (NetworkAPI.USER_INFO_0) Marshal.PtrToStructure(iter, typeof(NetworkAPI.USER_INFO_0));
iter = (IntPtr)((int) iter + Marshal.SizeOf(typeof(NetworkAPI.USER_INFO_0)));
listBox1.Items.Add(Users[i].Username);
}
NetworkAPI.NetApiBufferFree(bufPtr);
}
listBox1.SelectedIndex = 0;
}
Now just call EnumerateUsers inside Form_Load to populate them in your listbox at startup
private void Form1_Load(object sender, EventArgs e) {
EnumerateUsers();
}

And run it!

Hope that helps!