protected void WriteValue(VfpConstantExpression c)
{
if (c != null)
{
WriteValue(c.Value);
}
}
public override VfpExpression Visit(VfpConstantExpression expression)
{
switch (expression.ResultType.ToPrimitiveTypeKind())
{
case PrimitiveTypeKind.Binary:
case PrimitiveTypeKind.Decimal:
case PrimitiveTypeKind.Double:
case PrimitiveTypeKind.Single:
case PrimitiveTypeKind.String:
return(new VfpParameterExpression(expression.ResultType, GetParameterName(), expression));
default:
return(base.Visit(expression));
}
}
public override VfpExpression Visit(VfpProjectExpression expression)
{
VfpProjectExpression innerProjectionExpression;
bool hasNotExpression;
if (GetInnerProjectionExpression(expression, out innerProjectionExpression, out hasNotExpression))
{
var innerNewInstanceExpression = innerProjectionExpression.Projection as VfpNewInstanceExpression;
if (innerNewInstanceExpression != null)
{
var innerConstExpression = innerNewInstanceExpression.Arguments[0] as VfpConstantExpression;
if (innerConstExpression != null)
{
var countExpression = new VfpConstantExpression(innerConstExpression.ResultType, "COUNT(*)");
innerNewInstanceExpression = new VfpNewInstanceExpression(innerNewInstanceExpression.ResultType, new VfpExpressionList(new List <VfpExpression> {
countExpression
}));
innerProjectionExpression = new VfpProjectExpression(innerProjectionExpression.ResultType, innerProjectionExpression.Input, innerNewInstanceExpression);
VfpExpression comparison = new VfpComparisonExpression(VfpExpressionKind.LessThan,
PrimitiveTypeKind.Boolean.ToTypeUsage(),
new VfpConstantExpression(
PrimitiveTypeKind.Int32.ToTypeUsage(), 0),
innerProjectionExpression);
if (!hasNotExpression)
{
comparison = new VfpNotExpression(comparison.ResultType, comparison);
}
innerNewInstanceExpression = new VfpNewInstanceExpression(innerNewInstanceExpression.ResultType, new VfpExpressionList(new List <VfpExpression> {
comparison
}));
innerProjectionExpression = new VfpProjectExpression(expression.ResultType, expression.Input, innerNewInstanceExpression);
return(innerProjectionExpression);
}
}
}
return(base.Visit(expression));
}
public override VfpExpression Visit(VfpConstantExpression expression)
{
WriteValue(expression.Value);
return(expression);
}
private static bool IsZero(VfpConstantExpression expression)
{
return(expression != null && expression.Value != null && expression.Value.ToString() == "0");
}
public override VfpExpression Visit(VfpConstantExpression expression)
{
_expressions.Add(expression);
return(base.Visit(expression));
}
public virtual VfpExpression Visit(VfpConstantExpression expression)
{
return(expression);
}
