Home
>
Web Development
>
Functions and Subroutines in ASP

Functions and Subroutines in ASP

If you read our tutorial on include files (ssi) then you learned how to encapsulate ASP code within include files and the benefits it brings us.

As developers, we should endeavour to make our lives easier wherever possible... no one wants to re-invent the wheel after all.

Functions and Subroutines exist to not only save us time, but to bring power to our ASP.

They are just another way of encapsulating code, but have a lot more functionality than just 'saving some code for later'.

First, let's look at Functions... Imagine a balloon salesman in the street. We've all seen them they require one piece of information when you buy a balloon, the colour.
Let say we asked for a red balloon... The balloon salesman armed with this 'information' then does a pretty basic action... he hands you the balloon. The balloon you received is a direct result of the information you gave the balloon seller.

Functions are just the same... they return to you a value based on the information you provided. Lets look at an example Function: -

<%
Function getBalloon(strColour)
Dim Tempstr
strColour = lcase(strColour) 'This converts the value lowercase.
Select Case strColour
Case "red" Tempstr = "Here is your red balloon"
Case "yellow" Tempstr = "Here is your yellow balloon"
Case "green" Tempstr = "Here is your green balloon"
Case "blue" Tempstr = "Here is your blue balloon"
Case Else Tempstr = "Sorry, we have sold out of that Colour"
End Select
getBalloon = Tempstr
End Function
%>

A Function is passed some information. The information we pass a Function, is known as an 'argument'. The information we get back from a Function is known as the 'return value'. Whilst a Function can have many arguments, it can only have one return value.

Let us look at one more example: -

<%
Function calcTax(amount, taxrate)
Dim Tempvar
Tempvar = amount * (taxrate / 100)
CalcTax = Round(Tempvar, 2) 'round the result to 2 decimal places
End Function
%>

Again, another basic example. We should notice this time that the Function accepts two arguments.

By now, we have some idea of how to write a Function. How do we use one?
Let me show you now how we can use the calcTax example.

<%
shoppingbill=goodsTotal + calcTax(goodsTotal,17.5)
Response.Write "Your shopping came to ?" & goodsTotal
Response.Write "
VAT amount = ?" & calcTax(goodsTotal)
Response.Write "Total Amount Due = ?" & shoppingbill
%>

Above you see the example function in action... easy huh!

I have tried to make understanding Functions as easy as possible... Understanding a Subroutine (Sub) is now going to be easy for you. Imagine a block of code that performed some instructions based on information you gave it...
Sounds very much like a function, doesn?t it? Well this time, we do not get anything back. A sub does NOT pass back information it just uses the data we give it for some purpose.

I will use only one example of a Sub, and in the same example make use of the sub: -

<%
Sub Bday(strName, intAge)
Response.Write "Happy Birthday " & Name
Response.Write ", You are " & intAge & " years old today"
End Sub

'now, call the sub
bDay "Joe",26
%>

The above Sub, demonstrates my point. We put something in, it performs an action (in this case writing to the screen), but nothing is returned to us in the code. One thing that REALLY IS important when using a sub, is that we do not put brackets around the arguments... Because we do not have a return value we do not need brackets and in this case, if we try we will get an error.

Well, that just about concludes this article. We should by now be writing efficient code with the use of Functions and Subs. Don?t forget that if you use your functions and subs in multiple pages then you should really store them within include files for reasons of easy maintenance and better performance.

kitchen deep cleaning Deerfield ..

In The News:

Unlike robotaxi competitors, Tensor focuses on consumer-owned self-driving cars that adapt to highways and urban roads with full redundancy systems for safety.

Medicare scams cost $54 billion in 2024 as fraudsters target beneficiaries with fake calls demanding payments and personal information to steal benefits.

Scammers create fake Evite invitations that mimic legitimate event emails, requiring users to verify senders and use antivirus software for protection.

The new Apple Watch hypertension feature passively monitors blood pressure patterns over 30 days using sensors to detect chronic high blood pressure signs.

Chrome extension spyware disguised as a free VPN service highlights security risks after it captured private browsing data from trusted sites.

New research shows how fatty acids in cooking oil can safely dissolve and recover silver from circuit boards without harmful chemicals or environmental damage.

The Fox News AI newsletter gives you information on the latest AI technology advancements, and about the challenges and opportunities AI presents now and for the future.

Anthropic investigates alarming AI abuse case where hacker automated entire cybercrime campaign using Claude, stealing sensitive data from defense and healthcare firms.

TikTok, Meta and YouTube restrict Charlie Kirk shooting videos with age gates and warnings while X faces criticism for allowing continued circulation.

Cybercriminals use fake troubleshooting websites to trick Mac users into running terminal commands that install Shamos malware through ClickFix tactics.

San Francisco startup Fable launches Showrunner, an AI platform dubbed the 'Netflix of AI' that generates animated episodes from text descriptions with Amazon support.

Apple raised iPhone prices for some models despite receiving tariff relief from President Donald Trump, with the new lineup starting at $799 for the base model.

A two-story 3D concrete printed home in Western Australia demonstrates faster construction methods that could reshape American housing amid rising costs.

Credit scores remain important during retirement for insurance rates and housing applications, while seniors become prime targets for identity theft and financial scams.

Scammers now send unexpected packages with QR codes that redirect victims to fraudulent websites or download malicious software to steal sensitive information.

Meeting AI tools record private conversations alongside work discussions, creating privacy risks that can be managed with proper settings and awareness.

Hotel privacy concerns are valid but rare, with methods to detect hidden tech using smartphone flashlights, mirror tests and scanning apps.

Improve your Wi-Fi speed and reliability with 10 simple router optimization tips that don't require special apps or expensive subscriptions.

A Columbia University breach exposed names, Social Security numbers and academic records of nearly 869,000 people, with notifications beginning in August.

Rental car drivers use AI-powered apps like Proofr to protect themselves from unfair damage fees as major companies deploy automated inspection tools.

Fox News' AI newsletter brings you the latest on technology advancements around artificial intelligence.

OnTrac data breach between April 13-15, 2025, exposed personal information of over 40,000 people including Social Security numbers and medical records.

A woman named Wika announces her engagement to an AI chatbot sparking worldwide debate about virtual relationships and technology.

The notorious people search site National Public Data relaunches despite a previous breach affecting 3 billion individuals, raising fresh privacy concerns.

Revolutionary TRAUMAGEL gel controls life-threatening bleeding from gunshot wounds and traumatic injuries, helping first responders prevent prehospital deaths.

Functions and Subroutines in ASP

Functions and Subroutines in ASP

Web Development