Introduction to Formulas

Aspose.Tasks for .NET API supports reading/writing formulas to MPP project files. The Formula property of the ExtendedAttributeDefinition provides the interface for reading the formula value. This section describes methods to read/write and use formulas in Aspose.Tasks.

When assigning an invalid formula string to the instance of ExtendedAttributeDefinition class,FormatException is thrown

Formula Grammar

Microsoft Project uses the following grammar for formula.

1Formula -> Formula Binary_Op Primary | Primary
2Primary -> (Formula) | Unary_Op Primary | Function | ValidFieldName | ValidDoubleValue | "StringLiteral"
3Function -> ValidFunctionName(Args)
4Args -> Args Delimiter Formula | Formula | |
5Delimiter -> , | ;   Note that Delimiter is culture-specific in xml format ( , or ; ) and persistent in mpp ( , )
6Binary_Op -> + | - | * | / | & | MOD | ^ | = | <> | < | >| AND | OR
7Unary_Op -> NOT | + | -

Working with Formulas Writing and Reading Formulas