Surviving the basics
A drop down menu is the most popular way to cram a lot of links into a small space. A drop down menu
(also called a "drop down") is a list of web pages. The user selects one of the options and presses,
the choice that has been selected will then stay selected permanently. For example, this drop down
gives you three options:
The code for the basic drop down list is like this
| < SELECT NAME="search" style="width:200;" action ="http://www.insight2design.com/index.asp"> < OPTION VALUE="alatvista">Altavista < OPTION VALUE="google">Google < OPTION VALUE="lycos">Lycos < /OPTION> < /SELECT> |
Using Active Server Page's (ASP) to our advantage
Drop Downs are tremendously useful and they are commonly used for forms throughout the WWW. We can
use our new found programming language to our advantage to develop a easier way to manage our drop
down lists, and that method involves building a database
Firstly what we need to do is build our database to hold our information for the drop down list. In
this example we will build a drop down which will contain a list of countries around the world.
Our database table would look like:
| tbldropdown_country | ||
| Unid | Varchar_country | Show |
| Int - Identity | Varchar(50) | Int(4) |
Entering the information
Once the table has been built, we need to enter our information.
We enter into the second column each different country we need to enter and for each country we would
like to appear on the page we enter a 1 into the show column. For every country we do not want to appear
we enter a 0 in the show column. Something like this below.
| Unid | Varchar_country | Show |
| 1 | United Kingdom | 1 |
| 2 | United States Of America | 1 |
| 3 | France | 0 |
Developing our Active Server Page
Once the table has been built, start to build our ASP page. The below code is the top of the HTML code.
| < form method="post" name="countryform" action ="http://www.insight2design.com/index.asp" > < SELECT name=country > < option value=PS>Please Select</OPTION> |
Now we start to write out the ASP code.
| < % sTestSQL = "SELECT * FROM tbldropdown_country where show = 1 order by varchar_country asc" Set connTest = Server.CreateObject("ADODB.Connection") connTest.Open "dsn=mynewdsn;Uid=username;Pwd=password;" Set rsTest = connTest.Execute(sTestSQL) |
The variable sTestSQL set in the second line of the ASP code holds the SQL statement which will pull all the information out of the table we have previously created. The third line creates the server object for the database, whilst the fourth line specifies the link to our database using DSN . The last line of the code executes the SQL statement contained in sTestSQL on our table.
| Do While Not rsTest.EOF Response.Write "< Option value ='" & rsTest("varchar_country") & "' >" & _ rsTest("varchar_country") & "< /option "> rsTest.MoveNext Loop |
We know loop through all the values displaying the shown fields from our table. The ASP code not only displays the drop down information but also the drop down value. You can check this on the finished article by viewing the source and seeing if the two values are in the Option tag.
| Response.write "< /select >" rsTest.Close Set rsTest = Nothing connTest.Close Set connTest = Nothing %> < /form > < /table > < /BODY > < /HTML > |
The last lines of code finish off the drop down box. The Response.write line of the code closes the select tag, the second and third close the record set and four and five closes the database connection
Conclusion
The advantages of adding a database driven drop down list are as follows:
- Easy to maintain
- Saves replicating data, that is stored in a database, onto a HTML page
- More accurate
