asp.net user Registration verification

Asp.net| User Registration////Verify that the user name is the same as the duplicate in the registration database!!!
Private Sub Check_click (ByVal sender as System.Object, ByVal e as System.EventArgs) Handles check. Click
Dim MyConnection as OleDbConnection
Dim MyCommand as OleDbCommand
Dim dbname as String
dbname = Server.MapPath ("Db1.mdb")
MyConnection = New OleDbConnection ("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=c:\documents and Settings\ Administrator\my documents\visual Studio projects\webapplication1 (2) \database\db1.mdb ") The directory where the database resides

If UserID. Text = "" Then
Label5.text = "error!! You must complete it "
Else

Dim Checklogin as String
Checklogin = "SELECT * from Users"

Dim cmd as New OleDbCommand (Checklogin, MyConnection)
Dim Reader as OleDbDataReader

Try
Myconnection.open ()
reader = cmd. ExecuteReader ()
Reader. Read ()

If UserID. Text = Reader ("userid") Then
Label5.text = "The UserID had been used"
Else
Label5.text = "This userid can use"
End If
Catch Err as Exception
Trace.Write (Err. Message)
Label5.text = "Checked error"
Finally
If (not myconnection are nothing) Then
Myconnection.close ()
End If

End Try
End If
End Sub



User Registration
Private Sub Regist_click (ByVal sender as System.Object, ByVal e as System.EventArgs) Handles regist. Click
Dim MyConnection as OleDbConnection
Dim MyCommand as OleDbCommand
Dim dbname as String
dbname = Server.MapPath ("Db1.mdb")
MyConnection = New OleDbConnection ("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=c:\documents and Settings\ Administrator\my documents\visual Studio projects\webapplication1 (2) \database\db1.mdb ")
Dim Strinsert as String
Strinsert = "INSERT INTO Users ("
Strinsert &= "U_id,u_password)"
Strinsert &= "VALUES ('"
Strinsert &= userid. Text & "', '"
Strinsert &= password. Text & "')"
Dim cmd as New OleDbCommand (Strinsert, MyConnection)
Dim added as Integer
Try
Myconnection.open ()
Added = cmd. ExecuteNonQuery
If added > 0 Then
Label5.text = "Your information is added"
Response.Redirect ("Home.aspx")

End If
Catch Err as Exception
Trace.Write (Err. Message)
Label5.text = "added error"
Finally
If (not myconnection are nothing) Then
Myconnection.close ()
End If
End Try

End Sub


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