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ColdFusion Basics (Cont’d). 321483 02-14-2002. String, Date-time and Boolean Variables. In addition to numeric variables, ColdFusion can use string , date-time , and Boolean type variables ColdFusion provides a number of useful string, date-time, and Boolean functions. String Variables.
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ColdFusion Basics (Cont’d) 321483 02-14-2002
String, Date-time and Boolean Variables • In addition to numeric variables, ColdFusion can use string, date-time, and Boolean type variables • ColdFusion provides a number of useful string, date-time, and Boolean functions
String Variables • Strings: • Strings are groupings of text • String Variables: • String variables allow you to store text data • String variables follow the same naming conventions of numeric variables
String Variables and <CFSET> • You can assign a string variable a value using the CFSET tag • Example: <CFSET City=“Clarkson University"> “Clarkson University” is also called a string literal
String Variables and <CFSET> • If you want to include a quotation mark in a string you must type two together • Example: <CFSET Name="William ""Buck"" Rogers"> stores William "Buck" Rogers in Name
String variables and <CFOUTPUT> • String variables can be displayed just like numeric variables – using the CFOUTPUT tag and # • ColdFusion substitutes values of variables and functions enclosed in pound signs (#) in string literals • Quotation marks used in the CFSET tag are NOT displayed • They are delimiters for string literals and NOT part of the actual text
Using String Expressions • ColdFusion allows you to form string expressions by using string variables and a string operator • The most useful operator is concatenate (&) which connects one string to another • Example 1:<CFSET FirstName=“Koffi "><CFSET LastName=“N'Da"><CFSET FullName = FirstName & LastName> This stores the string “Koffi N’Da" in the FullName variable
Using String Expressions • Example 2: <CFSET PricePhrase="The price is #DollarFormat(Price)#"> store the phrase "The price is $1,300.00" in string variable PricePhrase, assuming numeric variable Price is 1300.00
Using String Expressions • Unlike other programming languages ColdFusion lets you create string literals that span multiple lines • Example: "Pet" is a valid string literal, the carriage returns are stored after each letter
String Functions Click here to have detailed information on string functions
Date-Time Values and Variables • You can also create variables in ColdFusion that store date and time values • Date and times can range from 100 A.D to 9999 A.D. • For more details on date-time functions: http://nongmon.compsci.buu.ac.th/cfdocs/CFML_Reference/
Creating a date-time Variable • You need to use the CreateDateTime function to create a new date-time variable • Click the link below for more information on the CreateDateTime function
Creating a date-time Variable • Example <CFSET LastUpdate = CreateDateTime(2003,5,19,14,15,50)> Assigns the date 5/19/2003 and time 14:15:50 to the date-time variable LastUpdate
Formatting a Date-time Variable • DateFormat Function • You can use the DateFormat and TimeFormat functions to change the way a date/time is displayed • Takes two parameters, a date-time value and a mask • The mask contains letters that signify different kinds of formatting • Click links below for syntaxes: • DateFormat syntax • TimeFormat syntax
Using DateFormat and TimeFormat • Examples • <CFOUTPUT>#DateFormat(LastUpdate,"mmmm d, yyyy")#</CFOUTPUT>Displays: May 1, 2003 • <CFOUTPUT>#TimeFormat(LastUpdate,"hh:mm:sstt")#</CFOUTPUT>Displays: 02:15:50PM
Date-Time Operations Click here to have detailed information on date-time functions
Boolean Variables • Boolean Data • Represents a status or a situation, such as True or False • Boolean Variables • A Boolean variable can store only two possible values : • True (Yes or On) • False (No or Off) • You can use Boolean variables where a program must take an action depending on a condition
Boolean Functions Click here to have detailed information on Boolean functions
Typeless Expression Evaluation • Unlike traditional programming languages ColdFusion can evaluate an expression even if operands and operators are of different types • Arguments are converted into required data types, as long as the data is reasonable