/// <summary>
/// Try to parse a line of CSV data. Can only return false if an unterminated text qualifier is encountered.
///
/// This function cannot recognize 'sep=' lines because it does not know whether it is parsing the first line
/// in the overall CSV stream.
/// </summary>
/// <returns>False if there was an unterminated text qualifier in the <paramref name="line"/></returns>
/// <param name="line">The line of text to parse</param>
/// <param name="settings">The CSV settings to use for this parsing operation (Default: CSV)</param>
/// <param name="row">The array of fields found in the line</param>
public static bool TryParseLine(string line, out string[] row, CSVSettings settings = null)
{
row = null;
var machine = new CSVStateMachine(settings);
while (machine.State == CSVState.CanKeepGoing)
{
row = machine.ParseChunk(line, true);
line = string.Empty;
}
return(machine.State == CSVState.Done);
}
/// <summary>
/// Parse a CSV stream into <![CDATA[ IEnumerable<string[]> ]]> asynchronously, while permitting embedded newlines
/// </summary>
/// <param name="inStream">The stream to read</param>
/// <param name="settings">The CSV settings to use for this parsing operation (Default: CSV)</param>
/// <returns>An enumerable object that can be examined to retrieve rows from the stream.</returns>
public static async IAsyncEnumerable <string[]> ParseStreamAsync(StreamReader inStream, CSVSettings settings = null)
{
var machine = new CSVStateMachine(settings);
while (machine.State == CSVState.CanKeepGoing)
{
var line = string.Empty;
if (!inStream.EndOfStream)
{
line = await inStream.ReadLineAsync();
}
var row = machine.ParseLine(line, inStream.EndOfStream);
if (row != null)
{
yield return(row);
}
}
}
/// <summary>
/// Parse a line from a CSV file and return an array of fields, or null if it fails
/// </summary>
/// <param name="line">One line of text from a CSV file</param>
/// <param name="settings">The CSV settings to use for this parsing operation (Default: CSV)</param>
/// <param name="throwOnFailure">If this value is true, throws an exception if parsing fails</param>
/// <returns>An array containing all fields in the next row of data, or null if it could not be parsed.</returns>
public static string[] ParseLine(string line, CSVSettings settings = null, bool?throwOnFailure = null)
{
string[] row = null;
var machine = new CSVStateMachine(settings);
while (machine.State == CSVState.CanKeepGoing)
{
row = machine.ParseChunk(line, true);
line = string.Empty;
}
// Anything other than success throws an error here
if (machine.State != CSVState.Done)
{
throw new Exception($"Malformed CSV structure: {machine.State}");
}
return(row);
}
