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Using Expressions (Reporting Services)

In Reporting Services, expressions are used throughout the report definition to specify or calculate values for parameters, queries, filters, report item properties, group and sort definitions, text box properties, bookmarks, document maps, dynamic page header and footer content, images, and dynamic data source definitions. This topic provides examples of the many places you can use expressions to vary the content or appearance of a report. This list is not comprehensive. You can set an expression for any property in a dialog box that displays the expression (fx) button or in a drop-down list that displays <Expression...>.

Expressions are written in Microsoft Visual Basic. An expression begins with an equal sign (=) followed by a combination of references to built-in collections such as dataset fields and parameters, constants, functions, and operators.

Using Simple Expressions

Simple expressions contain a reference to a single dataset field, parameter, or built-in field. Simple expressions appear on the design surface and in dialog boxes in brackets, for example, a dataset field appears as [ProductID]. Simple expressions are created for you automatically when you drag a field from a dataset onto a text box. A placeholder is created and the expression defines the underlying value. You can also type expressions directly into a data region cell or text box, both on the design surface or in a dialog box, (for example, [ProductID]).

The following table lists examples of the ways you can use simple expressions. The table describes the functionality, the property to set, the dialog box you typically use to set it, and the value for the property. You can type the simple expression directly on the design surface, in a dialog box, or in the Properties pane, or you can edit it in the Expression dialog box, just as you would with any expression.

Functionality

Property, Context, and Dialog Box

Property Value

Specify a dataset field to display in a text box.

Value property for a placeholder inside a text box. Use the Placeholder Properties Dialog Box, General.

[Sales]

Aggregate values for a group.

Value property for a placeholder inside a row associated with a Tablix group. Use the Text Box Properties Dialog Box, General.

[Sum(Sales)]

Include a page number.

Value property for a placeholder inside a text box that is placed in a page header. Use the Text Box Properties Dialog Box, General.

[&PageNumber]

Display a selected parameter value.

Value property for a placeholder inside a text box on the design surface. Use the Text Box Properties Dialog Box, General.

[@SalesThreshold]

Specify a group definition for a data region.

Group expression on the Tablix group. Use Tablix Group Properties Dialog Box, General.

[Category]

Exclude a specific field value from a table.

Filter equation on the Tablix. Use Tablix Properties Dialog Box, Filters.

For data type, select Integer.

[Quantity]

>

100

Include only a specific value for a group filter.

Filter equation on the Tablix group. Use Tablix Group Properties Dialog Box, Filters.

[Category]

=

Clothing

Exclude specific values for more than one field from a dataset.

Filter equation for a group in a Tablix. Use Tablix Properties Dialog Box, Filters.

=[Color]

<>

Red

=[Color]

<>

Blue

Specify sort order based on an existing field in a table.

Sort expression on the Tablix. Use Tablix Properties Dialog Box, Sorting.

[SizeSortOrder]

Link a query parameter to a report parameter.

Parameters collection on the dataset. Use Dataset Properties Dialog Box, Parameters.

[@Category]

[@Category]

Pass a parameter from a main report to a subreport.

Parameters collection on the subreport. Use Subreport Properties Dialog Box, Parameters.

[@Category]

[@Category]

For more examples, see Expression Examples (Reporting Services).

Using Complex Expressions

Complex expressions can contain multiple built-in references, operators, and function calls, and appear on the design surface as <<Expr>>. To see or change the expression text, you must open the Expression dialog box or type directly in the Properties pane. The following table lists typical ways you can use a complex expression to display or organize data or change report appearance, including the property to set, the dialog box you typically use to set it, and the value for the property. You can type an expression directly into a dialog box, on the design surface, or in the Properties pane.

Functionality

Property, Context, and Dialog Box

Property Value

Calculate aggregate values for a dataset.

Value property for a placeholder inside of a text box. Use the Placeholder Properties Dialog Box, General.

=First(Fields!Sales.Value,"DataSet1")

Concatenate text and expressions in the same text box.

Value for a placeholder inside of a text box that is placed in a page header or page footer. Use the Tablix Properties Dialog Box, Filters.

="This report began processing at " & Globals!ExecutionTime

Calculate an aggregate value for a dataset in a different scope.

Value for a placeholder inside of a text box that is placed in a Tablix group. Use the Tablix Properties Dialog Box, Filters.

=Max(Fields!Total.Value,"DataSet2)

Format data in a text box depending on value.

Color for a placeholder inside of a text box in the details row for a Tablix. Use the Text Box Properties Dialog Box, Font.

=IIF(Fields!TotalDue.Value < 10000,"Red","Black")

Calculate a value once to refer to throughout the report.

Value for a report variable. Use the Report Properties Dialog Box, Variables.

For more information about variables, see Using Report and Group Variables Collection References in Expressions (Reporting Services).

=Variables!MyCalculation.Value

Include specific values for more than one field from a dataset.

Filter equation for a group in a Tablix. Use the Tablix Properties Dialog Box, Filters.

For data type, select Boolean.

=IIF(InStr(Fields!Subcat.Value,"Shorts")=0 AND (Fields!Size.Value="M" OR Fields!Size.Value="S"),TRUE, FALSE)

=

TRUE

Hide a text box on the design surface, that can be toggled by the user using a Boolean parameter named Show.

Hiddenproperty on a text box. Use the Text Box Properties Dialog Box, Visibility.

=Not Parameters!Show<boolean parameter>.Value

Specify dynamic page header or footer content.

Value for a placeholder inside of a text box that is placed in the page header or footer. Use the Tablix Properties Dialog Box, Filters.

="Page " & Globals!PageNumber & " of " & Globals!TotalPages

Specify a data source dynamically by using a parameter.

Connection string on the Data source. Use the Data Source Properties Dialog Box, General.

="Data Source=" & Parameters!ServerName.Value & ";initial catalog=AdventureWorks"

Identify all the values for a multivalue parameter chosen by the user.

Value for a placeholder inside of a text box. Use the Tablix Properties Dialog Box, Filters.

=Join(Parameters!MyMultivalueParameter.Value,", ")

Specify page breaks for every 20 rows in a Tablix with no other groups.

Group expression for a group in a Tablix. Use the Tablix Group Properties Dialog Box, General.

PageBreak for the group in the Tablix. Use the Tablix Group Properties Dialog Box, Page Breaks. Set Between each instance of a group.

=Ceiling(RowNumber(Nothing)/20)

Specify conditional visibility based on a parameter.

Hidden property for a Tablix. Use the Tablix Properties Dialog Box, Visibility.

=Not Parameters!<boolean parameter>.Value

Specify a date formatted for a specific culture.

Value for a placeholder inside of a text box in a data region. Use the Text Box Properties Dialog Box, General.

=Fields!OrderDate.Value.ToString(System.Globalization.CultureInfo.CreateSpecificCulture("de-DE"))

Concatenate a string and a number formatted as a percentage to two decimal places.

Value for a placeholder inside of a text box in a data region. Use the Text Box Properties Dialog Box, General.

="Growth Percent: " & Format(Fields!Growth.Value,"p2")

For more examples, see Expression Examples (Reporting Services).