public static void WriteCsv
(
this DataView dataView,
TextWriter writer,
string fieldSeparator,
string recordSeparator,
IEnumerable <string> columnsToWrite = null
)
{
dataView.ThrowIfNull("dataView");
writer.ThrowIfNull("writer");
fieldSeparator.ThrowIfNull("fieldSeparator");
recordSeparator.ThrowIfNull("recordSeparator");
if (columnsToWrite == null || columnsToWrite.Count() == 0)
{
columnsToWrite = dataView.ColumnNames();
}
else
{
var unknownColumns = columnsToWrite.Except(dataView.ColumnNames(), StringComparer.OrdinalIgnoreCase);
if (unknownColumns.Count() > 0)
{
throw new ArgumentException("There are unknonwn columns.");
}
}
// Write column headings.
foreach (string column in columnsToWrite)
{
writer.Write(column);
writer.Write(fieldSeparator);
}
writer.Write(recordSeparator);
// Write data.
foreach (DataRowView row in dataView)
{
bool first = true;
foreach (string columnName in columnsToWrite)
{
var column = row[columnName];
if (!first)
{
writer.Write(fieldSeparator);
}
writer.Write(column.ToString());
first = false;
}
writer.Write(recordSeparator);
}
}
