# OSGeo::FDO::Expression::Expression Class Reference
[OSGeo::FDO::Expression]

Inheritance diagram for OSGeo::FDO::Expression::Expression:

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List of all members.

## Detailed Description

Expression is an abstract base class that forms the root of an expression tree. The Expression class contains operations for converting between the well defined text representation and the object representation of an expression.

()

## Public Member Functions
| Expression (System::IntPtr unmanaged, System::Boolean autoDelete)
| Constructs a Expression object based on an unmanaged instance of the object.
System::Void | Process (OSGeo::FDO::Expression::IExpressionProcessor *processor)
| Abstract operation that takes an IExpressionProcessor as an argument. Concrete expression subclasses must override this method and pass themselves as an argument to the appropriate expression processor operation.
System::String * | ToString ()
| Abstract operation that returns the well defined text representation of this expression.
## Static Public Member Functions
static OSGeo::FDO::Expression::Expression * | Parse (System::String *expressionText)
| Static operation that parses the specified text and returns an expression. An exception is thrown if the text does not conform to the well defined text representation of an expression.