internal static bool TryMatchPropertyEqualsValue(
DbExpression expression,
string propertyVariable,
out DbPropertyExpression property,
out object value)
{
property = (DbPropertyExpression)null;
value = (object)null;
if (expression.ExpressionKind != DbExpressionKind.Equals)
{
return(false);
}
DbBinaryExpression binaryExpression = (DbBinaryExpression)expression;
if (binaryExpression.Left.ExpressionKind != DbExpressionKind.Property)
{
return(false);
}
property = (DbPropertyExpression)binaryExpression.Left;
return(ViewSimplifier.TryMatchConstant(binaryExpression.Right, out value) && property.Instance.ExpressionKind == DbExpressionKind.VariableReference && !(((DbVariableReferenceExpression)property.Instance).VariableName != propertyVariable));
}
private static bool TryMatchConstant(DbExpression expression, out object value)
{
if (expression.ExpressionKind == DbExpressionKind.Constant)
{
value = ((DbConstantExpression)expression).Value;
return(true);
}
if (expression.ExpressionKind == DbExpressionKind.Cast && expression.ResultType.EdmType.BuiltInTypeKind == BuiltInTypeKind.PrimitiveType && ViewSimplifier.TryMatchConstant(((DbUnaryExpression)expression).Argument, out value))
{
PrimitiveType edmType = (PrimitiveType)expression.ResultType.EdmType;
value = Convert.ChangeType(value, edmType.ClrEquivalentType, (IFormatProvider)CultureInfo.InvariantCulture);
return(true);
}
value = (object)null;
return(false);
}
