User Authentication - Page 23

The User Authentication group of server behaviors contains four server behaviors that make creating a login extremely easy. Once we have a login set up, we will be able to restrict access to pages or even parts of pages. Let's create a login and play with these behaviors.

Log In User

This server behavior generates the entire code that will open a table, verify a user, and redirect him or her to a desired page. All we have to do is create the login form. The Log In User behavior also does something else – it creates one session by default and another optionally. The session created by default holds the username of the person logging in – it is called MM_Username.

You can also optionally make Dreamweaver MX set a session for the column that holds access levels. The session will be called MM_UserAuthorization.

Both of these sessions can be accessed later on with this code: Session("MM_Username") and Session("MM_UserAuthorization"). Before we begin, let's take a look at the database table that will store the users:

Login In User will authenticate the user by checking to see if the values submitted in the login form match the username and user_pwd columns. I have filled the user table with some values. You can add your own directly to the database, or create an Insert Record behavior (as we saw earlier in the chapter) to allow insertion of new login records from the Web.

Create a new dynamic ASP web page and save it as login.asp. Create a login form by inserting an empty form in the document – rename the form "frm_login", and insert a table with 3 rows and 2 columns inside the form. Type the text "username:" in the left column of the first row and "password:" in the left column of the second row. Insert textfields in the top and second rows of the right hand column. Name the username textfield "username", and the password textfield "user_pwd", as these are the names of the corresponding database columns. Select the password textfield and, from Properties, change the Type to Password. This will make sure that asterisks replace characters typed when the page is accessed live. This is important so that the password is always hidden even while logging in. Insert a button in the bottom row of the right-hand column – change the label of the button to "Login". The form should now look like this:

Add the Log In User behavior by selecting Server Behaviors > + > User Authentication > Log In User. Fill in the resulting dialog box so it looks exactly as shown here:

As you can see, we have selected access_group as the column to Get Level From – this will make the behavior create the optional session we talked about earlier, MM_UserAuthorization. It will hold the value of the access_group column for the successful user into a session (you can simply restrict access based solely on username and password, but for this example we will restrict based on Access Levels too). Hit OK.

Our Login application is complete, but before we test it in a browser, open the categories3.asp page. Select Bindings > Session Variable and type in MM_Username and click OK. You will now see the Session available under Bindings. This does nothing but make it easier for us to add the code Session("MM_Username") to our pages, to identify the user currently in session.

Somewhere at the top of this page type the text, "Welcome username!" Highlight the username text and select the MM_Username session from Bindings and click Insert (at the bottom of the Application Panel).

The username text should be replaced with the code <%=Session("MM_Username")%>. You can now test your login in a browser – load the login.asp page, type in "omar" for the username and "123456" as the password. You should be taken to the categories3.asp page.

Delete Record - Page 22
Dynamic Dreamweaver MX
Log Out User - Page 24