LDAP Search within Active Directory for authentication

Hi, I hope you guys can help me.

I need to build a form that request username and password on ASP not ASP.net (sorry to clarify but i got some responses in other forums in .net)

This form will send an LDAP query into the active directory located on a different server and it will check for existing users.

If the users exist they will be redirected to a new page. if not they will be prompt to try again for username and password.

Im not an experience programmer in asp, but in php. so I understand the logic. If you can point me to the right direction I will appreciate it.

 

//first add following lines to ur web.config, some of this will be irrelevant for ur ldap settings make appropraite changes
<appSettings>
<add key="ldapServer" value="LDAP://directory.name.com: _portnumber"/>
<add key="ldapSearch" value="ou=people,o=companyname,c=US"/>
<add key="ldapAttrUserId" value="uid"/>
</appSettings>

//create a c# class and then create a object and then call authenticate user
public class ldapAuthentication
{
private string _serverPath;
private string _searchPath;
private string _userAttr;

public ldapAuthentication()
{
_serverPath = ConfigurationManager.AppSettings["ldapServer"].ToString();
_searchPath = ConfigurationManager.AppSettings["ldapSearch"].ToString();
_userAttr = ConfigurationManager.AppSettings["ldapAttrUserId"].ToString();
}

public bool AuthenticateUser(string _userID, string _passWord)
{
bool _isValid = false;

if (_userID == null)
{
throw (new Exception("Please Enter User ID!"));
}

if (_passWord == null)
{
throw (new Exception("Enter Password!"));
}

//user id must supplied to search
if (_userID.Length < 1 || _passWord.Length < 1)
{
throw (new Exception("UserId and/or password are not Entered!"));
}

DirectoryEntry dirEntry = new DirectoryEntry(_serverPath + "/" + _searchPath);
dirEntry.AuthenticationType = AuthenticationTypes.ServerBind;
DirectorySearcher dirSearch = new DirectorySearcher(dirEntry);

dirSearch.Filter = "(" + _userAttr + "=" + _userID + ")";
SearchResult sr = dirSearch.FindOne();

try
{
if (null != sr)
{
dirEntry.Username = _userAttr + "=" + _userID + "," + _searchPath;
dirEntry.Password = _passWord;
dirEntry.AuthenticationType = AuthenticationTypes.ServerBind;
dirSearch.FindOne();
_isValid = true;
}
else
{
throw (new Exception("Invalid User ID"));
}
}
catch (Exception ex)
{
_isValid = false;
throw (new Exception("Invalid Password"));
}

dirSearch = null;
sr = null;

return _isValid;

}
}