Using hidden computed fields
Using hidden computed fields on a form is an easy way to provide information to @formulas and JavaScript that run in support of a form. Normally, hidden fields are collected at the top or the bottom of a form. Since some fields depend upon others, the order of fields on the form may be important, with dependent fields positioned after independent ones.
Hidden fields serve many purposes. Here is a sampling of how these fields can be used.
Add fields to provide access to key document attributes
Some document attributes can be retrieved by invoking @functions in formulas. There are, however, situations in which you cannot rely on @functions and formulas to return the correct information.
For example, the name of the form used to create a document is not available until after the document has been saved. If the name of the form is important to either a form formula, some JavaScript, or an agent invoked by the WebQuerySave event, then create a hidden Computed when composed...
