Programming ColdFusion MX, 2nd Edition

Preserving Input

In ColdFusion 5.0, a new attribute called preservedata was added to the cfform tag. Setting preservedata to Yes causes ColdFusion to retain and display data submitted from a cfinput, cftextinput, cfslider, or cftree control when a form is submitted to itself or to another page with like-named cfform controls. The exact effect of the preservedata attribute depends on the type of form control you use in your cfform. For cfinput and cftextinput controls, setting preservedata to Yes allows you to display the data entered by the user after the form has been submitted without any additional coding. For cfslider controls, the slider is set automatically to the position from the previous form post. For cftree controls, the tree expands automatically to the branch containing the previously selected item. For preservedata to work with a tree control, the completepath attribute of the cftree tag must be set to Yes.

Example 10-26 shows how the preservedata attribute works with each type of form control it is compatible with. Using CGI.Script_Name for the action attribute of the cfform tag causes the form to post to itself, regardless of the filename you use to save the file.

Example 10-26. Using the preservedata attribute of cfform

<cfform action="#CGI.Script_Name#" name="MyForm" preservedata="Yes" enctype="application/x-www-form-urlencoded"> <table> <tr> <td>cfinput (text):</td> <td><cfinput type="text" name="teex" size="10" maxlength="10"></td> </tr> <tr> <td>cfinput (password):</td> ...