private uint GetIdentifierCRC32(string identifier)
{
using (Stream stream = File.OpenRead(BuildFileName(identifier)))
{
return(CRC32Utility.GetCRC32(stream));
}
}
public void AsyncLoad()
{
try
{
uint cRC32 = 0;
if (System.IO.File.Exists(_fileName))
{
// compute the CRC of the existing file
using (FileStream stream = new FileStream(_fileName, FileMode.Open, FileAccess.Read))
cRC32 = CRC32Utility.GetCRC32(stream);
}
using
(
DAE.Runtime.Data.Row row = (DAE.Runtime.Data.Row)_process.Evaluate
(
String.Format
(
"LoadIfNecessary('{0}', {1})",
_document.Replace("'", "''"),
((int)cRC32).ToString()
),
null
)
)
{
if (!(bool)row["CRCMatches"])
{
Directory.CreateDirectory(Path.GetDirectoryName(_fileName));
using (Stream sourceStream = row.GetValue("Value").OpenStream())
using (FileStream targetStream = new FileStream(_fileName, FileMode.Create, FileAccess.Write))
StreamUtility.CopyStream(sourceStream, targetStream);
}
}
Session.SafelyInvoke(new AsyncFinishHandler(AsyncFinish), new object[] { true });
}
catch
{
Session.SafelyInvoke(new AsyncFinishHandler(AsyncFinish), new object[] { false });
// Don't allow exceptions to go unhandled... the framework will abort the application
}
}
public override object InternalExecute(Program program, object[] arguments)
{
IDataValue tempValue = arguments[0] as IDataValue;
if (tempValue == null)
{
tempValue = DataValue.FromNative(program.ValueManager, arguments[0]);
}
if (tempValue.IsPhysicalStreaming)
{
using (Stream stream = tempValue.OpenStream())
{
return((int)CRC32Utility.GetCRC32(stream));
}
}
else
{
byte[] physical = new byte[tempValue.GetPhysicalSize(true)];
tempValue.WriteToPhysical(physical, 0, true);
return((int)CRC32Utility.GetCRC32(physical));
}
}