/// <summary>
/// Parse the IsOf expression using <see cref="JsonElement"/>.
/// </summary>
/// <param name="element">The input JSON element.</param>
/// <param name="context">The parser context.</param>
/// <param name="isOfExp">The built IsOf expression.</param>
/// <returns>true/false</returns>
private static bool BuildIsOfExpression(JsonElement element, JsonParserContext context, out CsdlIsTypeExpression isOfExp)
{
Debug.Assert(context != null);
isOfExp = null;
// Is-of expressions are represented as an object with a member $IsOf whose value is an annotation expression,
JsonElement propertyValue;
if (element.ValueKind != JsonValueKind.Object || !element.TryGetProperty("$IsOf", out propertyValue))
{
return(false);
}
// whose value is an annotation expression,
CsdlExpressionBase expression = propertyValue.ProcessProperty("$IsOf", context, ParseExpression);
// a member $Type whose value is a string containing an qualified type name, and optionally a member $Collection with a value of true.
// If the specified type is a primitive type or a collection of primitive types,
// the facet members $MaxLength, $Unicode, $Precision, $Scale, and $SRID MAY be specified if applicable to the specified primitive type.
// If the facet members are not specified, their values are considered unspecified.
CsdlTypeReference typeReference = CsdlJsonParseHelper.ParseCsdlTypeReference(element, context);
isOfExp = new CsdlIsTypeExpression(typeReference, expression, context.Location());
return(true);
}
/// <summary>
/// Parse the Cast expression using <see cref="JsonElement"/>.
/// </summary>
/// <param name="element">The input JSON element.</param>
/// <param name="context">The parser context.</param>
/// <param name="castExp">The built cast expression.</param>
/// <returns>true/false.</returns>
private static bool TryParseCastExpression(JsonElement element, JsonParserContext context, out CsdlCastExpression castExp)
{
Debug.Assert(context != null);
castExp = null;
// Cast expressions are represented as an object with a member $Cast
JsonElement propertyValue;
if (element.ValueKind != JsonValueKind.Object || !element.TryGetProperty("$Cast", out propertyValue))
{
return(false);
}
// with a member $Cast whose value is an annotation expression
CsdlExpressionBase expression = propertyValue.ProcessProperty("$Cast", context, ParseExpression);
// a member $Type whose value is a string containing the qualified type name, and optionally a member $Collection with a value of true.
CsdlTypeReference typeReference = CsdlJsonParseHelper.ParseCsdlTypeReference(element, context);
castExp = new CsdlCastExpression(typeReference, expression, context.Location());
return(true);
}
