/// <summary>
/// Stores that data in the given stream.
/// </summary>
/// <param name="reader">The data reader.</param>
/// <param name="writer">The writer.</param>
/// <param name="readerFileSetting">The file.</param>
/// <param name="cancellationToken">The cancellation token.</param>
/// <returns>
/// Number of rows written
/// </returns>
protected void DataReader2Stream(IDataReader reader, TextWriter writer,
CancellationToken cancellationToken)
{
Contract.Requires(reader != null);
Contract.Requires(writer != null);
var columnInfos = GetColumnInformation(reader);
var enumerable = columnInfos.ToList();
if (enumerable.IsEmpty())
{
throw new ApplicationException("No columns defined to be written.");
}
var recordEnd = m_StructuredWriterFile.FileFormat.NewLine.Replace("CR", "\r").Replace("LF", "\n").Replace(" ", "")
.Replace("\t", "");
HandleWriteStart();
var numEmptyRows = 0;
var numColumns = enumerable.Count();
var
sb = new StringBuilder(1024); // Assume a capacity of 1024 characters to start , data is flushed every 512 chars
if (!string.IsNullOrEmpty(m_StructuredWriterFile.Header))
{
sb.Append(ReplacePlaceHolder(m_StructuredWriterFile.Header));
if (!m_StructuredWriterFile.Header.EndsWith(recordEnd, StringComparison.Ordinal))
{
sb.Append(recordEnd);
}
}
var withHeader = m_StructuredWriterFile.Row;
var colNum = 0;
foreach (var columnInfo in enumerable)
{
var placeHolder = string.Format(System.Globalization.CultureInfo.CurrentCulture, cHeaderPlaceholder, colNum);
if (m_StructuredWriterFile.XMLEncode)
{
withHeader = withHeader.Replace(placeHolder, HTMLStyle.XmlElementName(columnInfo.Header));
}
else if (m_StructuredWriterFile.JSONEncode)
{
withHeader = withHeader.Replace(placeHolder, HTMLStyle.JsonElementName(columnInfo.Header));
}
else
{
withHeader = withHeader.Replace(placeHolder, columnInfo.Header);
}
colNum++;
}
withHeader = withHeader.Trim();
while (reader.Read() && !cancellationToken.IsCancellationRequested)
{
NextRecord();
if (sb.Length > 512)
{
writer.Write(sb.ToString());
sb.Length = 0;
}
// Start a new line
sb.Append(recordEnd);
var emptyColumns = 0;
var row = withHeader;
colNum = 0;
foreach (var columnInfo in enumerable)
{
Contract.Assume(columnInfo != null);
var placeHolder1 = string.Format(System.Globalization.CultureInfo.CurrentCulture, cFieldPlaceholderByNumber, colNum);
var value = string.Empty;
var placeHolder2 = string.Format(System.Globalization.CultureInfo.CurrentCulture, cFieldPlaceholderByName, columnInfo.Header);
var col = reader.GetValue(columnInfo.ColumnOridinalReader);
if (col == DBNull.Value)
{
emptyColumns++;
}
else
{
value = TextEncodeField(m_StructuredWriterFile.FileFormat, col, columnInfo, false, reader, null);
if (m_StructuredWriterFile.XMLEncode)
{
value = SecurityElement.Escape(value);
}
else if (m_StructuredWriterFile.JSONEncode)
{
value = HTMLStyle.JsonEncode(value);
}
}
row = row.Replace(placeHolder1, value).Replace(placeHolder2, value);
colNum++;
}
if (emptyColumns == numColumns)
{
numEmptyRows++;
}
else
{
sb.Append(row);
numEmptyRows = 0;
}
}
sb.Append(ReplacePlaceHolder(m_StructuredWriterFile.Footer));
writer.Write(sb.ToString());
}
/// <summary>
/// Writes the specified file reading from the given reader
/// </summary>
/// <param name="reader">A Data Reader with the data</param>
/// <param name="output">The output.</param>
/// <param name="cancellationToken">The cancellation token.</param>
protected override async Task WriteReaderAsync([NotNull] IFileReader reader, [NotNull] Stream output,
CancellationToken cancellationToken)
{
using (var writer = new StreamWriter(output, new UTF8Encoding(true), 4096))
{
SetColumns(reader);
var numColumns = Columns.Count();
if (numColumns == 0)
{
throw new FileWriterException("No columns defined to be written.");
}
var recordEnd = NewLine;
HandleWriteStart();
// Header
if (!string.IsNullOrEmpty(Header))
{
var sbH = new StringBuilder();
sbH.Append(Header);
if (!Header.EndsWith(recordEnd, StringComparison.Ordinal))
{
sbH.Append(recordEnd);
}
await writer.WriteAsync(sbH.ToString()).ConfigureAwait(false);
}
// Static template for the row, built once
var withHeader = m_Row;
var colNum = 0;
var placeHolderLookup1 = new Dictionary <int, string>();
var placeHolderLookup2 = new Dictionary <int, string>();
foreach (var columnInfo in Columns)
{
var placeHolder = string.Format(CultureInfo.CurrentCulture, c_HeaderPlaceholder, colNum);
if (m_XMLEncode)
{
withHeader = withHeader.Replace(placeHolder, HTMLStyle.XmlElementName(columnInfo.Name));
}
else if (m_JSONEncode)
{
withHeader = withHeader.Replace(placeHolder, HTMLStyle.JsonElementName(columnInfo.Name));
}
else
{
withHeader = withHeader.Replace(placeHolder, columnInfo.Name);
}
placeHolderLookup1.Add(colNum, string.Format(CultureInfo.CurrentCulture, c_FieldPlaceholderByNumber, colNum));
placeHolderLookup2.Add(colNum,
string.Format(CultureInfo.CurrentCulture, cFieldPlaceholderByName, columnInfo.Name));
colNum++;
}
withHeader = withHeader.Trim();
var
sb = new StringBuilder(
1024); // Assume a capacity of 1024 characters to start, data is flushed every 512 chars
while (await reader.ReadAsync(cancellationToken).ConfigureAwait(false) &&
!cancellationToken.IsCancellationRequested)
{
NextRecord();
// Start a new line
sb.Append(recordEnd);
var row = withHeader;
colNum = 0;
foreach (var value in from columnInfo in Columns
let col = reader.GetValue(columnInfo.ColumnOrdinal)
select m_XMLEncode
? SecurityElement.Escape(TextEncodeField(FileFormat, col, columnInfo, false,
reader,
null))
: JsonConvert.ToString(col))
{
row = row.Replace(placeHolderLookup1[colNum], value).Replace(placeHolderLookup2[colNum], value);
colNum++;
}
sb.Append(row);
if (sb.Length <= 512)
{
continue;
}
await writer.WriteAsync(sb.ToString()).ConfigureAwait(false);
sb.Length = 0;
}
if (sb.Length > 0)
{
await writer.WriteAsync(sb.ToString()).ConfigureAwait(false);
}
// Footer
if (!string.IsNullOrEmpty(Footer()))
{
await writer.WriteAsync(Footer()).ConfigureAwait(false);
}
await writer.FlushAsync();
}
}