The Container report control is a container for other items. There are a number of ways in which you can use it to enhance your reports.
Visual Groupings
You can place report controls within the Container to group them visually, and to make it easier at design time to move a group of report controls.
Note: Drawing a container around existing items does not contain them. Instead you must drag the items into the container.
You can use a container as a border for your report pages, and set border properties to create purely visual effects within your report, and even display an image behind a group of report controls by setting the BackgroundImage property of the Container.
Anchoring Items
Probably the best usage of the Container report control is to anchor report controls which may otherwise be pushed down by a vertically expanding data region. For example, if you have a group of textboxes below a table with some of them to the left or right, any of them directly below the table are pushed down below the expanded table at run time, while the upper textboxes remain where you placed them at design time. To prevent this from happening, place the group of textboxes within a container.
Container Dialog
Properties for the Container are available in the Container dialog. To open it, with the Container control selected on the report, under the Properties Window, click the Property dialog link.
The Container dialog lets you set properties on the report control with the following pages.
General
Name: Enter a name for the container that is unique within the report. This name can be called in code. You can only use underscore (_) as a special character in the Name field. Other special characters such as period (.), space ( ), forward slash (/), back slash (\), exclamation (!), and hyphen (-) are not supported.
Page breaks:
- Insert a page break before this container: Insert a page break before the container.
- Insert a page break after this container: Insert a page break after the container.
Appearance
Background
Color: Select a color to use for the background of the container.
Image: Enter an image to use for the background of the container.
Border
Style: Select a style for the border.
Width: Enter a value in points to set the width of the border.
Color: Select a color to use for the border, or select the <Expression...> option to open the Expression Editor and create an expression that evaluates to a .NET color.
Rounded Rectangle: Specify the radius for each corner of the shape independently. Drag the handlers 
available at each corner of the shape to set the value of the radius at each corner.
Visibility
Initial visibility
- Visible: The container is visible when the report runs.
- Hidden: The container is hidden when the report runs.
- Expression: Use an expression with a Boolean result to decide whether the container is visible. True for hidden, False for visible.
Visibility can be toggled by another report control: Select this check box to display a toggle image next to another report control. This enables the drop-down box below where you can specify the TextBox control that toggles the visibility of the container. The user can click the toggle item to show or hide this container.
Navigation
Document map label: Enter an expression to use as a label to represent this item in the table of contents (document map).
Bookmark ID: Enter an expression to use as a locator for this container. You will then be able to provide a bookmark link to this item from another report control using a Jump to bookmark action.
Data Output
The Data Output page of the Container dialog allows you to control the following properties when you export to XML:
- Element name: Enter a name to be used in the XML output for this container.
- Output: Choose Auto, Yes, No, or Contents only to decide whether to include the contents of this container in the XML output. Choosing Auto exports the contents of the container only when the value is not a constant.