Programming ColdFusion

Variables

A variable is a name associated with a data value; it is common to say that a variable stores or contains a value. Variables allow you to store and manipulate data in your applications; they are called variables because the values they represent can change throughout the life of an application. In ColdFusion, you don’t have to explicitly declare your variables, as you do in a language such as C++. Additionally, ColdFusion variables are typeless, meaning that you can assign a value of any datatype (string, numeric, Boolean, object, etc.) to any variable.

Variable Names

The following rules and guidelines apply to variable names in CFML:

• Variable names must begin with a letter and can contain only letters, numbers, and the underscore character. Variable names can’t contain spaces. For example, Test, MyVariable, My_variable, MyVariable1, and MyDescriptive_var2 are all valid ColdFusion variables, while 4C, My Variable, Phone#, and A/P aren’t.

• Avoid using variable names that may be reserved words in SQL, such as Time, Date, and Order.

• Avoid using variable names that are the same as ColdFusion variable scopes: Application, Attribute, Caller, CGI, Client, Cookie, Form, Variable, Request, Server, Session, URL, and Query.

• Avoid choosing variable names that end in _date, _eurodate, _float, _integer, _range, _required, or _time, as these are reserved suffixes for server-side form validation variables and can cause naming conflicts.

• ColdFusion variable names aren’t case-sensitive. ...