# HideRule

Defines a visibility rule for a report item in a kind of output format.

### Description

The visibility rule says when a report item should be hidden. It can be hidden based on the output type, an expression, or both. For example, the browser control is normally hidden in all output formats except HTML. A past-due item might be hidden if the account is not past due.

An item can be completely hidden (hidden in all formats), or hidden only in selected formats. An item hidden in all formats is never actually created in the Factory. An item hidden in selected formats is created, but will be omitted when rendered to the format for which it is hidden.

## format

Identifies the format in which the element should be hidden.

### Description

This property identifies the output format in which to hide the element. The element can be hidden in all output formats (using the "All" choice), or in a specific format. If the element is hidden in all formats, then it is not created in the Factory. Otherwise, is created, but is removed before rendering in the Presentation engine when converted to the target output format.

## valueExpr

A boolean expression that determines whether to hide the element or not.

### Description

The boolean expression to evaluate. If the expression evaluates to `true`, then the element is hidden; Otherwise, the element is not hidden. Default to `true` if no expression is given.