Detect if a local user/group account exists

[Roshan]

Hi,

Given a name, I want to be able to detect if a user or a group account
exists with that name on a system and know if its a user or a group. My
search yielded the "LookupAccountName" Win32 API but I haven't found
any class in .NET that allows me to do that.

Does any one know of a class in .NET or a way of doing this without
using Win32 APIs ?

Thanks,
Roshan Achar

[Henning Krause [MVP]]

Hello,

I think, a quick hack would be this:

public bool GroupExists(string name) {
try
{
NTAccount account = new NTAccount(name);
acc.Translate(typeof(SecurityIdentifier));
return true;
}
catch (PrincipalNotMappedException)
{
return false;
}
}

Not very elegant, though.

Best regards,
Henning Krause

"Roshan" <br*****@gmail.com> wrote in message
news:11**********************@u72g2000cwu.googlegr oups.com...

Hi,

Given a name, I want to be able to detect if a user or a group account
exists with that name on a system and know if its a user or a group. My
search yielded the "LookupAccountName" Win32 API but I haven't found
any class in .NET that allows me to do that.

Does any one know of a class in .NET or a way of doing this without
using Win32 APIs ?

Thanks,
Roshan Achar

[Roshan]

Thanks Henning.

This will suffice for the moment. It would have been better if an API
existed to do this directly.Also the Exception thrown is
IdentityNotMappedException
I found that I can detect if the name is a user or a group using

SecurityIdentifier.IsAccountSid(). It returns true if the name is a
local user account and false if its a group.

Thanks,
Roshan

Henning Krause [MVP] wrote:

Hello,

I think, a quick hack would be this:

public bool GroupExists(string name) {
try
{
NTAccount account = new NTAccount(name);
acc.Translate(typeof(SecurityIdentifier));
return true;
}
catch (PrincipalNotMappedException)
{
return false;
}
}

Not very elegant, though.

Best regards,
Henning Krause

"Roshan" <br*****@gmail.com> wrote in message
news:11**********************@u72g2000cwu.googlegr oups.com...

Hi,

Given a name, I want to be able to detect if a user or a group account
exists with that name on a system and know if its a user or a group. My
search yielded the "LookupAccountName" Win32 API but I haven't found
any class in .NET that allows me to do that.

Does any one know of a class in .NET or a way of doing this without
using Win32 APIs ?

Thanks,
Roshan Achar

[Knut Wehrle]

Hi Henning,

I've been looking for this for a long time. But it solves just one problem
for me.
I want to test if a group exists, and if not, I want to create it.

How can i do this?

Any idea?
"Henning Krause [MVP]" <ne***************@this.infinitec.de> schrieb im
Newsbeitrag news:uA**************@TK2MSFTNGP04.phx.gbl...

Hello,

I think, a quick hack would be this:

public bool GroupExists(string name) {
try
{
NTAccount account = new NTAccount(name);
acc.Translate(typeof(SecurityIdentifier));
return true;
}
catch (PrincipalNotMappedException)
{
return false;
}
}

Not very elegant, though.

Best regards,
Henning Krause

"Roshan" <br*****@gmail.com> wrote in message
news:11**********************@u72g2000cwu.googlegr oups.com...

Hi,

Given a name, I want to be able to detect if a user or a group account
exists with that name on a system and know if its a user or a group. My
search yielded the "LookupAccountName" Win32 API but I haven't found
any class in .NET that allows me to do that.

Does any one know of a class in .NET or a way of doing this without
using Win32 APIs ?

Thanks,
Roshan Achar

[Roshan]

Hi Knut,

You can create a group as follows

using (DirectoryEntry AD = new DirectoryEntry("WinNT://" +
Environment.MachineName + ",computer"))
{
try
{
String typeName = "group";
String accountName = "KnutGroup";
using (DirectoryEntry NewUser =
AD.Children.Add(accountName, typeName))
{
NewUser.CommitChanges();
}
}
catch
{
Console.WriteLine("Error occured");
}
}

Hope this suffices,

Thanks,
Roshan

Knut Wehrle wrote:

Hi Henning,

I've been looking for this for a long time. But it solves just one problem
for me.
I want to test if a group exists, and if not, I want to create it.

How can i do this?

Any idea?
"Henning Krause [MVP]" <ne***************@this.infinitec.de> schrieb im
Newsbeitrag news:uA**************@TK2MSFTNGP04.phx.gbl...

Hello,

I think, a quick hack would be this:

public bool GroupExists(string name) {
try
{
NTAccount account = new NTAccount(name);
acc.Translate(typeof(SecurityIdentifier));
return true;
}
catch (PrincipalNotMappedException)
{
return false;
}
}

Not very elegant, though.

Best regards,
Henning Krause

"Roshan" <br*****@gmail.com> wrote in message
news:11**********************@u72g2000cwu.googlegr oups.com...

Hi,

Given a name, I want to be able to detect if a user or a group account
exists with that name on a system and know if its a user or a group. My
search yielded the "LookupAccountName" Win32 API but I haven't found
any class in .NET that allows me to do that.

Does any one know of a class in .NET or a way of doing this without
using Win32 APIs ?

Thanks,
Roshan Achar

[Knut Wehrle]

Hi Roshan,

that's great!!! Thank you!
I've been looking for the solution very long.

Best Regards
Knut

"Roshan" <br*****@gmail.comschrieb im Newsbeitrag
news:11**********************@r2g2000cwb.googlegro ups.com...

Hi Knut,

You can create a group as follows

using (DirectoryEntry AD = new DirectoryEntry("WinNT://" +
Environment.MachineName + ",computer"))
{
try
{
String typeName = "group";
String accountName = "KnutGroup";
using (DirectoryEntry NewUser =
AD.Children.Add(accountName, typeName))
{
NewUser.CommitChanges();
}
}
catch
{
Console.WriteLine("Error occured");
}
}

Hope this suffices,

Thanks,
Roshan

Knut Wehrle wrote:

>Hi Henning,

I've been looking for this for a long time. But it solves just one
problem
for me.
I want to test if a group exists, and if not, I want to create it.

How can i do this?

Any idea?
"Henning Krause [MVP]" <ne***************@this.infinitec.deschrieb im
Newsbeitrag news:uA**************@TK2MSFTNGP04.phx.gbl...

Hello,

I think, a quick hack would be this:

public bool GroupExists(string name) {
try
{
NTAccount account = new NTAccount(name);
acc.Translate(typeof(SecurityIdentifier));
return true;
}
catch (PrincipalNotMappedException)
{
return false;
}
}

Not very elegant, though.

Best regards,
Henning Krause

"Roshan" <br*****@gmail.comwrote in message
news:11**********************@u72g2000cwu.googlegr oups.com...
Hi,

Given a name, I want to be able to detect if a user or a group account
exists with that name on a system and know if its a user or a group.
My
search yielded the "LookupAccountName" Win32 API but I haven't found
any class in .NET that allows me to do that.

Does any one know of a class in .NET or a way of doing this without
using Win32 APIs ?

Thanks,
Roshan Achar