At one time or another we've all had to wrestle with how to prevent users from hitting the Refresh button when a form ACTION page is being displayed so as to prevent the form from being resubmitted. One simple solution is to never actually display the ACTION page, instead, once the processing is...
and are both used to abort ColdFusion processing, but when used in with Custom Tags they are not alike at all. While terminates all request processing, gives developers far greater control over what happens after the abort greatly simplifying error checking, validation, and tag feedback. As a rule,...
Most developers know they can refer to query.RecordCount to obtain the number of records retrieved by a query, many even know that they can access query.CurrentRow to access the current row in an output loop and query.ColumnList for a list of retrieved columns. But here's one that many developers...
provides a scripting interface to parts of CFML - a syntax similar to that of JavaScript. Even comments within a block use the JavaScript comment format. But unlike JavaScript, is case-insensitive (like CFML itself). (Applies to: ColdFusion 4 (or later))
ColdFusion supports a single shared Custom Tag directory per server - not one per application. Until this feature is added the workaround is to use to invoke Custom Tags instead of the syntax. Using absolute and relative paths to Custom Tags may be provided allowing access to tags outside the...
Cookies are a very useful technology and an important part of any developers toolbox. But lots of hype and paranoia have contributed to many users fearing and disabling support for them. As such, you must never assume that just because you set a cookie it'll be there - always check for it's...
allows developers to create several types of loop, including a range loop (FROM a value TO a value). The values passed to FROM and TO may be any expression, but pay special attention when you use expressions that could change mid-loop - ColdFusion will ignore any new values and will only evaluate...
When designing your databases ensure that every table has a primary key so that every row in every table has a column (or set of columns) that uniquely identifies it. While primary keys are not actually required, experienced database designers ensure that every table they create has a primary key...
When is an array element not an array element? When it has never been used or initialized. ColdFusion expands arrays dynamically and as needed. So if you assign a value to array[2] after you create the array, ColdFusion will create elements 1 and 2 for you. But only element 2 will be a valid...
Structures cannot be copies using simple assignments (as in ), do that and you'll find that when the contents of one structure change, so do the contents of the other. To safely copy structures you must use the StructCopy() function. (Applies to: ColdFusion 4.5 (or later))