[c#] Connect to network drive with user name and password

How do I supply credential so that I can connect to a network drive in .NET?

I’m trying to retrieve files from a network drive and need to supply user credentials to access the drive.

var fileName = "Mylogs.log";
var local = Path.Combine(@"C:\TempLogs", fileName);
var remote = Path.Combine(@"\\servername\c$\Windows\Temp\", fileName);

WebClient request = new WebClient();
request.Credentials = new NetworkCredential(@"username", "password");

if (File.Exists(local))
{
    File.Delete(local);

    File.Copy(remote, local, true);
}
else
{
    File.Copy(remote, local, true);
}

you can use system.diagnostocs.process to call out to 'net use .... with userid and password' or to a command shell that takes those.

You can use the WindowsIdentity class (with a logon token) to impersonate while reading and writing files.

var windowsIdentity = new WindowsIdentity(logonToken);
using (var impersonationContext = windowsIdentity.Impersonate()) {
    // Connect, read, write
}

You can use WebClient class to connect to the network driver using credentials. Include the below namespace:

using System.Net;

WebClient request = new WebClient();
request.Credentials = new NetworkCredential("domain\username", "password");
string[] theFolders = Directory.GetDirectories(@"\\computer\share");

I really don't know the hidden process, but I use a webrequest, this way I'm able to pass the credentials, and it worked perfectly for me.

var ftpDownloadFile = WebRequest.Create("filePath");
ftpDownloadFile.Method = WebRequestMethods.Ftp.DownloadFile;
ftpDownloadFile.Credentials = new NetworkCredential("user", "pass");
using (var reader = (FtpWebResponse)ftpDownloadFile.GetResponse())
using (var responseStream = reader.GetResponseStream())
{
    var writeStream = new FileStream(Path.Combine(LocalStorage), FileMode.Create);
    const int length = 2048;
    var buffer = new Byte[length];
    if (responseStream != null)
    {
        var bytesRead = responseStream.Read(buffer, 0, length);
        while (bytesRead > 0)
        {
            writeStream.Write(buffer, 0, bytesRead);
            bytesRead = responseStream.Read(buffer, 0, length);
        }
    }
    reader.Close();
    writeStream.Close();
}

Use this code for Impersonation its tested in MVC.NET maybe for dot net core it required some change, If you want to dot net core let me know I will share.

 public static class ImpersonationAuthenticationNew
    {
        [DllImport("advapi32.dll", SetLastError = true)]
        private static extern bool LogonUser(string usernamee, string domain, string password, LogonType dwLogonType, LogonProvider dwLogonProvider, ref IntPtr phToken);
        [DllImport("kernel32.dll")]
        private static extern bool CloseHandle(IntPtr hObject);
        public static bool Login(string domain,string username, string password)
        {                
            IntPtr token = IntPtr.Zero;
            var IsSuccess = LogonUser(username, domain, password, LogonType.LOGON32_LOGON_NEW_CREDENTIALS, LogonProvider.LOGON32_PROVIDER_WINNT50, ref token);
            if (IsSuccess)
            {
                using (WindowsImpersonationContext person = new WindowsIdentity(token).Impersonate())
                {
                    var xIdentity = WindowsIdentity.GetCurrent();
                    #region Start ImpersonationContext  Scope
                    try
                    {

                        // TYPE YOUR CODE HERE 

                    }
                    catch (Exception ex) { throw (ex); }
                    finally {
                        person.Undo();
                        CloseHandle(token);
                        return true;
                    }
                    #endregion
                }
            }
            return false;
        }
    }

    #region Enums
    public enum LogonType
    {
        /// <summary>
        /// This logon type is intended for users who will be interactively using the computer, such as a user being logged on  
        /// by a terminal server, remote shell, or similar process.
        /// This logon type has the additional expense of caching logon information for disconnected operations;
        /// therefore, it is inappropriate for some client/server applications,
        /// such as a mail server.
        /// </summary>
        LOGON32_LOGON_INTERACTIVE = 2,

        /// <summary>
        /// This logon type is intended for high performance servers to authenticate plaintext passwords.

        /// The LogonUser function does not cache credentials for this logon type.
        /// </summary>
        LOGON32_LOGON_NETWORK = 3,

        /// <summary>
        /// This logon type is intended for batch servers, where processes may be executing on behalf of a user without
        /// their direct intervention. This type is also for higher performance servers that process many plaintext
        /// authentication attempts at a time, such as mail or Web servers.
        /// The LogonUser function does not cache credentials for this logon type.
        /// </summary>
        LOGON32_LOGON_BATCH = 4,

        /// <summary>
        /// Indicates a service-type logon. The account provided must have the service privilege enabled.
        /// </summary>
        LOGON32_LOGON_SERVICE = 5,

        /// <summary>
        /// This logon type is for GINA DLLs that log on users who will be interactively using the computer.
        /// This logon type can generate a unique audit record that shows when the workstation was unlocked.
        /// </summary>
        LOGON32_LOGON_UNLOCK = 7,

        /// <summary>
        /// This logon type preserves the name and password in the authentication package, which allows the server to make
        /// connections to other network servers while impersonating the client. A server can accept plaintext credentials
        /// from a client, call LogonUser, verify that the user can access the system across the network, and still
        /// communicate with other servers.
        /// NOTE: Windows NT:  This value is not supported.
        /// </summary>
        LOGON32_LOGON_NETWORK_CLEARTEXT = 8,

        /// <summary>
        /// This logon type allows the caller to clone its current token and specify new credentials for outbound connections.
        /// The new logon session has the same local identifier but uses different credentials for other network connections.
        /// NOTE: This logon type is supported only by the LOGON32_PROVIDER_WINNT50 logon provider.
        /// NOTE: Windows NT:  This value is not supported.
        /// </summary>
        LOGON32_LOGON_NEW_CREDENTIALS = 9,
    }
    public enum LogonProvider
    {
        /// <summary>
        /// Use the standard logon provider for the system.
        /// The default security provider is negotiate, unless you pass NULL for the domain name and the user name
        /// is not in UPN format. In this case, the default provider is NTLM.
        /// NOTE: Windows 2000/NT:   The default security provider is NTLM.
        /// </summary>
        LOGON32_PROVIDER_DEFAULT = 0,
        LOGON32_PROVIDER_WINNT35 = 1,
        LOGON32_PROVIDER_WINNT40 = 2,
        LOGON32_PROVIDER_WINNT50 = 3
    }
    #endregion

Use this code for Impersonation its tested in MVC.NET maybe for dot net core it required some change, If you want to dot net core let me know I will share.

 public static class ImpersonationAuthenticationNew
    {
        [DllImport("advapi32.dll", SetLastError = true)]
        private static extern bool LogonUser(string usernamee, string domain, string password, LogonType dwLogonType, LogonProvider dwLogonProvider, ref IntPtr phToken);
        [DllImport("kernel32.dll")]
        private static extern bool CloseHandle(IntPtr hObject);
        public static bool Login(string domain,string username, string password)
        {                
            IntPtr token = IntPtr.Zero;
            var IsSuccess = LogonUser(username, domain, password, LogonType.LOGON32_LOGON_NEW_CREDENTIALS, LogonProvider.LOGON32_PROVIDER_WINNT50, ref token);
            if (IsSuccess)
            {
                using (WindowsImpersonationContext person = new WindowsIdentity(token).Impersonate())
                {
                    var xIdentity = WindowsIdentity.GetCurrent();
                    #region Start ImpersonationContext  Scope
                    try
                    {

                        // TYPE YOUR CODE HERE 
                      return true;
                    }
                    catch (Exception ex) { throw (ex); }
                    finally {
                        person.Undo();
                        CloseHandle(token);
                       
                    }
                    #endregion
                }
            }
            return false;
        }
    }

    #region Enums
    public enum LogonType
    {
        /// <summary>
        /// This logon type is intended for users who will be interactively using the computer, such as a user being logged on  
        /// by a terminal server, remote shell, or similar process.
        /// This logon type has the additional expense of caching logon information for disconnected operations;
        /// therefore, it is inappropriate for some client/server applications,
        /// such as a mail server.
        /// </summary>
        LOGON32_LOGON_INTERACTIVE = 2,

        /// <summary>
        /// This logon type is intended for high performance servers to authenticate plaintext passwords.

        /// The LogonUser function does not cache credentials for this logon type.
        /// </summary>
        LOGON32_LOGON_NETWORK = 3,

        /// <summary>
        /// This logon type is intended for batch servers, where processes may be executing on behalf of a user without
        /// their direct intervention. This type is also for higher performance servers that process many plaintext
        /// authentication attempts at a time, such as mail or Web servers.
        /// The LogonUser function does not cache credentials for this logon type.
        /// </summary>
        LOGON32_LOGON_BATCH = 4,

        /// <summary>
        /// Indicates a service-type logon. The account provided must have the service privilege enabled.
        /// </summary>
        LOGON32_LOGON_SERVICE = 5,

        /// <summary>
        /// This logon type is for GINA DLLs that log on users who will be interactively using the computer.
        /// This logon type can generate a unique audit record that shows when the workstation was unlocked.
        /// </summary>
        LOGON32_LOGON_UNLOCK = 7,

        /// <summary>
        /// This logon type preserves the name and password in the authentication package, which allows the server to make
        /// connections to other network servers while impersonating the client. A server can accept plaintext credentials
        /// from a client, call LogonUser, verify that the user can access the system across the network, and still
        /// communicate with other servers.
        /// NOTE: Windows NT:  This value is not supported.
        /// </summary>
        LOGON32_LOGON_NETWORK_CLEARTEXT = 8,

        /// <summary>
        /// This logon type allows the caller to clone its current token and specify new credentials for outbound connections.
        /// The new logon session has the same local identifier but uses different credentials for other network connections.
        /// NOTE: This logon type is supported only by the LOGON32_PROVIDER_WINNT50 logon provider.
        /// NOTE: Windows NT:  This value is not supported.
        /// </summary>
        LOGON32_LOGON_NEW_CREDENTIALS = 9,
    }
    public enum LogonProvider
    {
        /// <summary>
        /// Use the standard logon provider for the system.
        /// The default security provider is negotiate, unless you pass NULL for the domain name and the user name
        /// is not in UPN format. In this case, the default provider is NTLM.
        /// NOTE: Windows 2000/NT:   The default security provider is NTLM.
        /// </summary>
        LOGON32_PROVIDER_DEFAULT = 0,
        LOGON32_PROVIDER_WINNT35 = 1,
        LOGON32_PROVIDER_WINNT40 = 2,
        LOGON32_PROVIDER_WINNT50 = 3
    }
    #endregion

The best way to do this is to p/invoke WNetUseConnection.

[StructLayout(LayoutKind.Sequential)] 
private class NETRESOURCE
{ 
        public int dwScope = 0;
        public int dwType = 0;
        public int dwDisplayType = 0;
        public int dwUsage = 0;
        public string lpLocalName = "";
        public string lpRemoteName = "";
        public string lpComment = "";
        public string lpProvider = "";
}


[DllImport("Mpr.dll")] 
private static extern int WNetUseConnection(
            IntPtr hwndOwner,
            NETRESOURCE lpNetResource,
            string lpPassword,
            string lpUserID,
            int dwFlags,
            string lpAccessName,
            string lpBufferSize,
            string lpResult
        );

Example code here.

Very elegant solution inspired from this one. This one uses only .Net library and does not need to use any command line or Win32 API.

Code for ready reference:

NetworkCredential theNetworkCredential = new NetworkCredential(@"domain\username", "password");
CredentialCache theNetCache = new CredentialCache();
theNetCache.Add(new Uri(@"\\computer"), "Basic", theNetworkCredential);
string[] theFolders = Directory.GetDirectories(@"\\computer\share");