Technical Analysis of asp.net simple single sign-on

The Code is as follows: Copy codeThe Code is as follows: // Single Sign On)
Public void SSOMethods (string username, string password)
{
// This method is omitted to determine logon conditions ......
Int result = CheckLogin (username, password );
If (result> 0)
{
// Unique ID, which can be set by yourself
String key = string. Format ("{0 }_{ 1}", username, password );
// Obtain the key value in the Cache.
String userCache = Cache [key]. ToString ();
// Judge whether it is null
If (string. IsNullOrEmpty (userCache ))
{
TimeSpan SessionTimeOut = new TimeSpan (0, 0, HttpContext. Current. Session. TimeOut, 0, 0 );
HttpContext. Current. Cache. Insert (key, key, null, DateTime. MaxValue, SessionTimeOut, CacheItemPriority, NotRemovable, null );
Session ["User"] = key;
Response. Write ("<font color = red> logon successful! </Font> ");
}
Else
{
Repsonse. Write ("<font color = red> sorry, you have logged on elsewhere! </Font> ");
Return;
}
}
Else
{
Response. Write ("the user name does not exist! ");
}
}