public Task <string> ReadStringAsync(IStorableFileInfo fileInfo)
{
using (var rs = fileInfo.CreateReadStream())
using (var sr = new StreamReader(rs))
{
return(sr.ReadToEndAsync());
}
}
/// <summary>
/// 异步写入字符串。
/// </summary>
/// <param name="fileInfo">给定的 <see cref="IStorableFileInfo"/>。</param>
/// <param name="content">给定的写入字符串。</param>
/// <returns>返回 <see cref="Task"/>。</returns>
public Task WriteStringAsync(IStorableFileInfo fileInfo, string content)
{
using (var rs = fileInfo.CreateReadStream())
using (var sw = new StreamWriter(rs))
{
return(sw.WriteAsync(content));
}
}
public async Task ReadAsync(IStorableFileInfo fileInfo, Stream writeStream,
CancellationToken cancellationToken = default)
{
if (writeStream.CanSeek)
{
writeStream.Seek(0, SeekOrigin.Begin);
}
using (var rs = fileInfo.CreateReadStream())
{
var processingSize = 0L;
var processingSpeed = 0L;
var beginSecond = DateTime.Now.Second;
var readLength = 0;
var buffer = new byte[Options.WebFile.BufferSize];
while ((readLength = await rs.ReadAsync(buffer, 0, buffer.Length).DisableAwaitContext()) > 0)
{
await writeStream.WriteAsync(buffer, 0, readLength, cancellationToken).DisableAwaitContext();
processingSize += readLength;
processingSpeed += readLength;
if (ProgressAction is not null)
{
var endSecond = DateTime.Now.Second;
if (beginSecond != endSecond)
{
processingSpeed = processingSpeed / (endSecond - beginSecond);
}
ProgressAction(new StorageProgressDescriptor
{
ContentLength = fileInfo.Length,
StartPosition = 0,
ProcessingSize = processingSize,
ProcessingSpeed = processingSpeed,
ProcessingPercent = Math.Max((int)(processingSize * 100 / fileInfo.Length), 1)
});
if (beginSecond != endSecond)
{
beginSecond = DateTime.Now.Second;
processingSpeed = 0;
}
}
}
}
}