/// <summary>
/// Tries to extract the WellKnownTextSQL portion from an astoria spatial literal.
/// </summary>
/// <param name="spatialLiteral">The spatial literal.</param>
/// <param name="prefix">The prefix.</param>
/// <param name="wellKnownTextSql">The well known text SQL.</param>
/// <returns>true if the extract was successful, false otherwise.</returns>
private static bool TryExtractWellKnownTextSqlFromSpatialLiteral(string spatialLiteral, string prefix, out string wellKnownTextSql)
{
var worked = WebConvert.TryRemovePrefix(prefix, ref spatialLiteral);
if (!worked)
{
wellKnownTextSql = null;
return(false);
}
worked = WebConvert.TryRemoveQuotes(ref spatialLiteral);
if (!worked)
{
wellKnownTextSql = null;
return(false);
}
wellKnownTextSql = spatialLiteral;
return(true);
}
private static bool QuotesAreValid(string text)
{
return(WebConvert.TryRemoveQuotes(ref text));
}
private Expression PromoteExpression(Expression expr, Type type, bool exact, bool isTypeCast = false)
{
Debug.Assert(expr != null, "expr != null");
Debug.Assert(type != null, "type != null");
if (expr.Type == type)
{
return(expr);
}
ConstantExpression ce = null;
if (type == typeof(DateTime))
{
// Sometimes if the property type is DateTime? in provider, we pass the type as DateTimeOffset?
// to ODataLib and it puts a Convert node to convert DateTimeOffset to DateTimeOffset?. Hence
// to reach to the constant value, we need to handle the Convert node.
if (expr.Type == typeof(DateTimeOffset) || expr.Type == typeof(DateTimeOffset?))
{
if (expr.NodeType == ExpressionType.Convert)
{
ce = ((UnaryExpression)expr).Operand as ConstantExpression;
}
}
}
if (ce == null)
{
ce = expr as ConstantExpression;
}
if (ce != null)
{
if (ce == ExpressionUtils.NullLiteral)
{
if (WebUtil.TypeAllowsNull(type))
{
return(Expression.Constant(null, type));
}
}
else
{
string text;
if (this.literals.TryGetValue(ce, out text))
{
Type target = WebUtil.GetNonNullableType(type);
object value = null;
if (ce.Type == typeof(string) && (target == typeof(Type) || target == typeof(ResourceType)))
{
// No qoutes required when the function is a cast
if (isTypeCast || WebConvert.TryRemoveQuotes(ref text))
{
ResourceType resourceType = this.tryResolveResourceType(text);
if (resourceType != null)
{
if (target == typeof(Type))
{
if (resourceType.CanReflectOnInstanceType)
{
value = resourceType.InstanceType;
}
}
else
{
if (resourceType.CanReflectOnInstanceType == false)
{
value = resourceType;
}
}
}
}
}
else if ((type == typeof(DateTime) || type == typeof(DateTime?)) &&
(expr.Type == typeof(DateTimeOffset) || expr.Type == typeof(DateTimeOffset?)))
{
// Since the URI parser in ODataLib will always convert Constants as DateTimeOffset,
// and WCF DS Server supports DateTime clr type, we need to do the conversion whenever required.
value = WebUtil.ConvertDateTimeOffsetToDateTime((DateTimeOffset)ce.Value);
}
else
{
switch (Type.GetTypeCode(ce.Type))
{
case TypeCode.Int32:
case TypeCode.Int64:
value = ParseNumber(text, target);
break;
case TypeCode.Double:
if (target == typeof(decimal))
{
value = ParseNumber(text, target);
}
break;
}
}
if (value != null)
{
return(Expression.Constant(value, type));
}
}
}
}
if (IsCompatibleWith(expr.Type, type))
{
// (type != typeof(object) || expr.Type.IsValueType) part is added
// to prevent cast to System.Object from non-value types (objects).
if (type.IsValueType || exact && (type != typeof(object) || expr.Type.IsValueType))
{
return(Expression.Convert(expr, type));
}
return(expr);
}
// Allow promotion from nullable to non-nullable by directly accessing underlying value.
if (WebUtil.IsNullableType(expr.Type) && type.IsValueType)
{
Expression valueAccessExpression = Expression.Property(expr, "Value");
valueAccessExpression = this.PromoteExpression(valueAccessExpression, type, exact, isTypeCast);
return(valueAccessExpression);
}
return(null);
}
