static void Test(string[] args)
{
// Creating the first dynamic number.
dynamic number = new DynamicNumber();
// Creating properties and setting their values
// for the dynamic number.
// The TrySetMember method is called.
number.Textual = "One";
number.Numeric = 1;
// Printing out properties. The TryGetMember method is called.
Console.WriteLine(
number.Textual + " " + number.Numeric);
dynamic negativeNumber = new DynamicNumber();
// Performing a mathematical negation.
// TryUnaryOperation is called.
negativeNumber = -number;
Console.WriteLine(
negativeNumber.Textual + " " + negativeNumber.Numeric);
// The following statement produces a run-time exception
// because the unary plus operation is not implemented.
// negativeNumber = +number;
}
// Perform the unary operation.
public override bool TryUnaryOperation(
UnaryOperationBinder binder, out object result)
{
// The Textual property contains
// the name of the unary operation in addition
// to the textual representaion of the number.
string resultTextual =
binder.Operation + " " +
dictionary["Textual"].ToString();
int resultNumeric;
// Determining what type of operation is being performed.
switch (binder.Operation)
{
case ExpressionType.Negate:
resultNumeric =
-(int)dictionary["Numeric"];
break;
default:
// In case of any other unary operation,
// print out the type of operation and return false,
// which means that the language should determine
// what to do.
// (Usually the language just throws an exception.)
Console.WriteLine(
binder.Operation +
": This unary operation is not implemented");
result = null;
return(false);
}
dynamic finalResult = new DynamicNumber();
finalResult.Textual = resultTextual;
finalResult.Numeric = resultNumeric;
result = finalResult;
return(true);
}