T DoRead <T>(TypeHandler handler)
{
ReadColumnLenIfNeeded();
if (_columnLen == -1)
{
// TODO: What actual exception to throw here? Oracle throws InvalidCast, SqlClient throws its
// own SqlNullValueException
throw new InvalidCastException("Column is null");
}
var result = handler.Read <T>(_buf, _columnLen);
_leftToReadInDataMsg -= _columnLen;
_columnLen = int.MinValue; // Mark that the (next) column length hasn't been read yet
_column++;
return(result);
}
T DoRead <T>(TypeHandler handler)
{
try {
ReadColumnLenIfNeeded();
if (_columnLen == -1)
{
throw new InvalidCastException("Column is null");
}
var result = handler.Read <T>(_buf, _columnLen);
_leftToReadInDataMsg -= _columnLen;
_columnLen = int.MinValue; // Mark that the (next) column length hasn't been read yet
_column++;
return(result);
} catch {
_connector.Break();
Cleanup();
throw;
}
}
T DoRead <T>(TypeHandler handler)
{
try {
ReadColumnLenIfNeeded();
if (_columnLen == -1)
{
throw new InvalidCastException("Column is null");
}
// TODO: Duplication with NpgsqlDataReader.GetFieldValueInternal
T result;
// The type handler supports the requested type directly
var tHandler = handler as ITypeHandler <T>;
if (tHandler != null)
{
result = handler.Read <T>(_buf, _columnLen, false).Result;
}
else
{
var t = typeof(T);
if (!t.IsArray)
{
throw new InvalidCastException($"Can't cast database type {handler.PgDisplayName} to {typeof(T).Name}");
}
// Getting an array
// We need to treat this as an actual array type, these need special treatment because of
// typing/generics reasons (there is no way to express "array of X" with generics
var elementType = t.GetElementType();
var arrayHandler = handler as ArrayHandler;
if (arrayHandler == null)
{
throw new InvalidCastException($"Can't cast database type {handler.PgDisplayName} to {typeof(T).Name}");
}
if (arrayHandler.GetElementFieldType() == elementType)
{
result = (T)handler.ReadAsObject(_buf, _columnLen, false).Result;
}
else if (arrayHandler.GetElementPsvType() == elementType)
{
result = (T)handler.ReadPsvAsObject(_buf, _columnLen, false).Result;
}
else
{
throw new InvalidCastException($"Can't cast database type {handler.PgDisplayName} to {typeof(T).Name}");
}
}
_leftToReadInDataMsg -= _columnLen;
_columnLen = int.MinValue; // Mark that the (next) column length hasn't been read yet
_column++;
return(result);
} catch {
_connector.Break();
Cleanup();
throw;
}
}
