本文整理汇总了C#中CsvReader.AssertNotNull方法的典型用法代码示例。如果您正苦于以下问题:C# CsvReader.AssertNotNull方法的具体用法?C# CsvReader.AssertNotNull怎么用?C# CsvReader.AssertNotNull使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类CsvReader
的用法示例。
在下文中一共展示了CsvReader.AssertNotNull方法的1个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C#代码示例。
示例1: FillAsync
/// <summary>
/// Populates <paramref name="this"/> with data read asynchronously from <paramref name="csvReader"/>.
/// </summary>
/// <remarks>
/// <para>
/// If <paramref name="this"/> has columns defined, those columns will be used when populating the data. If no columns have been defined, <paramref name="csvReader"/> must have a
/// <see cref="HeaderRecord"/>, which is then used to define the columns for <paramref name="this"/>. If any data record has more values than can fit into the columns defined on
/// <paramref name="this"/>, an exception is thrown.
/// </para>
/// </remarks>
/// <param name="this">
/// The <see cref="DataTable"/>.
/// </param>
/// <param name="csvReader">
/// The <see cref="CsvReader"/>.
/// </param>
/// <param name="maximumRecords">
/// The maximum number of records to read and add to <paramref name="this"/>.
/// </param>
/// <returns>
/// The number of rows added to <paramref name="this"/> (and therefore the number of data records read from <paramref name="csvReader"/>).
/// </returns>
public async static Task<int> FillAsync(this DataTable @this, CsvReader csvReader, int? maximumRecords)
{
@this.AssertNotNull("@this");
csvReader.AssertNotNull("csvReader");
exceptionHelper.ResolveAndThrowIf(maximumRecords.GetValueOrDefault() < 0, "maximumRecordsMustBePositive");
if (@this.Columns.Count == 0)
{
// table has no columns, so we need to use the CSV header record to populate them
exceptionHelper.ResolveAndThrowIf(csvReader.HeaderRecord == null, "noColumnsAndNoHeaderRecord");
foreach (var columnName in csvReader.HeaderRecord)
{
@this.Columns.Add(columnName);
}
}
var remaining = maximumRecords.GetValueOrDefault(int.MaxValue);
var buffer = new DataRecord[16];
while (remaining > 0)
{
var read = await csvReader.ReadDataRecordsAsync(buffer, 0, Math.Min(buffer.Length, remaining)).ConfigureAwait(false);
if (read == 0)
{
// no more data
break;
}
for (var i = 0; i < read; ++i)
{
var record = buffer[i];
exceptionHelper.ResolveAndThrowIf(record.Count > @this.Columns.Count, "moreValuesThanColumns", @this.Columns.Count, record.Count);
var recordAsStrings = new string[record.Count];
record.CopyTo(recordAsStrings, 0);
@this.Rows.Add(recordAsStrings);
}
remaining -= read;
}
return maximumRecords.GetValueOrDefault(int.MaxValue) - remaining;
}