CalculatedField.Expression Property
Specifies the expression of the current calculated field.
Namespace: DevExpress.Snap.Core.API
Assembly: DevExpress.Snap.v21.2.Core.dll
NuGet Package: DevExpress.Snap.Core
Declaration
Property Value
| Type | Description |
|---|---|
| String | A String value. |
Remarks
Use the Expression property to specify the expression for the calculated field. In the Snap project, this property provides access to the Expression Editor.
For expressions, numerous date-time, logical, math and string functions, operators and constants are supported. For a complete list of these functions, refer to Expressions.
To refer to a data field (returned by the CalculatedField.DataSource and CalculatedField.DataMember properties) within an expression, enclose its name in [square brackets]. Parameters are inserted using the “Parameters.” prefix before their names.
Date-time constants must be wrapped in #hashes# ([OrderDate] >= #1/1/2009#). To represent a null reference (one that does not refer to any object), use a question mark ([Region] != ?). And, to denote strings, use ‘apostrophes‘, otherwise, an error occurs.
The type of value returned by a calculated field is defined by its CalculatedField.FieldType property.
A calculated field’s expression cannot evaluate the values of other calculated fields.
Related GitHub Examples
The following code snippet (auto-collected from DevExpress Examples) contains a reference to the Expression property.
Note
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