/// <summary>
/// This method tries to determine whether given list of cells contain
/// all and only header names.
/// </summary>
/// <remarks>
/// The order of headers does not matter in this validation because of
/// it only checks whether all the header names are included. Further,
/// each name comparison is done by ignoring upper and lower cases.
/// </remarks>
/// <param name="headers">
/// The list of cells to be verified, which should contain header names.
/// </param>
/// <param name="descriptors">
/// The list of descriptors representing a single line.
/// </param>
/// <returns>
/// True is returned when all header names have occurred at least once,
/// no matter at which position a header name has occurred. Otherwise,
/// false is returned.
/// </returns>
private static Boolean IsHeaderLine(List <String> headers, List <ItemDescriptor> descriptors)
{
Int32 verified = 0;
for (Int32 index = 0; index < headers.Count; index++)
{
foreach (ItemDescriptor descriptor in descriptors)
{
if (CsvImporter <TInstance> .IsHeaderName(headers[index], false, descriptor))
{
verified++;
break;
}
}
}
return(verified == headers.Count);
}
/// <summary>
/// This method tries to validate given headers by applying exact
/// validation rules.
/// </summary>
/// <remarks>
/// Exact validation rules means in detail that each string in given headers
/// must exactly match its corresponding header name. Furthermore, exactly
/// match means that each header name is compared by applying a case-sensitive
/// name check. It also means that each header position must be the same
/// position which is defined within given descriptors.
/// </remarks>
/// <param name="headers">
/// The list of header names to be validated.
/// </param>
/// <param name="descriptors">
/// The list of descriptors representing a single line.
/// </param>
/// <exception cref="FormatException">
/// This exception is thrown as soon as one of the header validation rules
/// has been violated.
/// </exception>
/// <exception cref="ArgumentOutOfRangeException">
/// This exception might be thrown if accessing the lists fails.
/// </exception>
private static void ValidateHeader(List <String> headers, List <ItemDescriptor> descriptors)
{
// Keep in mind, the column validation has already checked the column count. And it is trusted
// in that an Argument Out Of Range Exception is thrown if there was a made mistake beforehand.
for (Int32 index = 0; index < headers.Count; index++)
{
String header = headers[index];
ItemDescriptor descriptor = descriptors[index];
if (!CsvImporter <TInstance> .IsHeaderName(header, true, descriptor))
{
throw new FormatException(
$"Header validation mismatch. Header name \"{header}\" at column {index} does not fit " +
$"to the expected header name \"{CsvImporter<TInstance>.GetHeaderName(descriptor)}.\"");
}
}
}
