An Introduction to Cold Fusion

An Introduction to Cold Fusion
K. Yue copyright 2000
Created: November 8, 2000

Introduction

Cold Fusion is a server side scripting application server comparable to ASP.
The latest version of Cold Fusion server from Allaire is 4.5. The version at UHCL is 4.0.
A Cold Fusion file has the extension .cfm.
When a user requests a .cfm file, the Web server invokes the Cold Fusion application server which reads and processes the .cfm file to create dynamic HTML contents.
Cold Fusion supports the Cold Fusion Markup Language (CFML)
CFML allows the uses of cold fusion meta-tag for server-side scripting and for simplification of certain tasks.

Basic CFML tags

The CF element <cfset> allows the setting of a CF variable.
The CF element <cfoutput> is used to display the results of a database query or other operations.
A Cold Fusion expression is interpreted with CFOUTPUT if it is enclosed by a pair of "#".

Example:

ip.cfm: Listing the IP address of the user.

<body bgcolor="#ccccff">
<span style="size:+2">
My First Cold Fusion Page:
<p>
<cfset RemoteIPAddress = CGI.REMOTE_ADDR>
<cfoutput>
Your IP Address is: #RemoteIPAddress#
</cfoutput>
</span>
</body>

The only CFML tags that can be used within a CFOUTPUT are the followings: CFSET, CFIF, CFELSE, CFELSEIF.

HTTP Parameters

HTTP parameters are passed automatically into predefined variables.
For parameter key using the Get method, refer to url.key.
For parameter name using the Post method, refer to form.key.

Example:

SimpleForm.cfm: present a simple form with client side validation and Java's applet.

<HTML>
<HEAD><TITLE>MY FORM</TITLE>
<SCRIPT LANGUAGE="JAVASCRIPT">

</SCRIPT>
</HEAD>

<BODY BGCOLOR=#FFFFCC>
<H2>My form</H2>

<P>
<CFFORM Name=BirthdayForm
        Action=SFProc.cfm>
Your name:
<CFINPUT Text="text"
         Name="Name"
         Value=""
         Required="Yes"
         Size="30"
         Maxlength="40">
<br>
Your birthday:
<CFINPUT Text="text"
         Name="Birthday"
         Value=""
         Required="Yes"
         Validate="date"
         Message="You must enter a date in mm/dd/yy format"
         Size="10"
         Maxlength="10">
<br>
Your IQ:
<CFINPUT Text="text"
         Name="IQ"
         Value=""
         Required="Yes"
         Validate="integer"
         Range="0,300"
         OnError="IQRangeError"
         Size="30"
         Maxlength="40">
<br>

Your favorite celebrities:
<br>
<CFTREE Name="favorite"
        Required="Yes"
        HScroll="yes"
        VScroll="yes"
        Width=300
        Height=200>
   <CFTREEITEM VALUE="celebrity">
      <CFTREEITEM Value="Movie Stars" Parent="celebrity">
         <CFTREEITEM Value="Clint Eastwood" Parent="Movie Stars">
         <CFTREEITEM Value="Julia Roberts" Parent="Movie Stars">
         <CFTREEITEM Value="Robert Redford" Parent="Movie Stars">
         <CFTREEITEM Value="Tom Hanks" Parent="Movie Stars">
         <CFTREEITEM Value="Godzilla" Parent="Movie Stars">
      <CFTREEITEM Value="Sport Stars" Parent="celebrity">
         <CFTREEITEM Value="Michael Jordan" Parent="Sport Stars">
         <CFTREEITEM Value="Magic Johnson" Parent="Sport Stars">
         <CFTREEITEM Value="Larry Bird" Parent="Sport Stars">
         <CFTREEITEM Value="Hakeem Olajuwon" Parent="Sport Stars">
</CFTREE>
<p>
<INPUT TYPE=SUBMIT>
<INPUT TYPE=RESET>
</CFFORM>

SimpeFormProcessing: processing the HTTP parameters.

<HTML>
<HEAD><TITLE>A Simple CFML Form's Example</TITLE></HEAD>

<BODY BGCOLOR=FFFFCC>
<FONT COLOR=BLUE>
<H2>Result of simple CFML form submission</H2>
</FONT>

<CFOUTPUT>
Hello, <FONT COLOR=BLUE>#Form.NAME#</FONT>.<br>
Your birthday is <FONT COLOR=BLUE>#Form.BIRTHDay#</FONT>.<br>
Your IQ is <FONT COLOR=BLUE>#Form.IQ#</FONT>.<br>
Your favorite celebrity is <FONT COLOR=BLUE>#Form.favorite.node#</FONT>.<br>
Interesting. Interesting.
</CFOUTPUT>
</BODY>
</HTML>