c# – sqlFileStream System.ComponentModel.Win32Exception：不

我正在尝试使用以下代码创建一个存储过程CLR,用于将文件插入到文件流中.

using System;
using System.Data;
using System.Data.SqlClient;
using System.Data.SqlTypes;
using Microsoft.SqlServer.Server;
using System.IO;
using System.Security.Principal;

public partial class StoredProcedures
{
     [Microsoft.SqlServer.Server.SqlProcedure]
     public static void sp_fileController(String friendlyName,String filePath)
{
    SqlParameter fDataParam = new System.Data.SqlClient.SqlParameter("@fData",SqlDbType.VarBinary,-1);
    SqlParameter fNameParam = new System.Data.SqlClient.SqlParameter("@fName",SqlDbType.NVarChar,300);

    WindowsIdentity newId = SqlContext.WindowsIdentity;
    WindowsImpersonationContext impersonatedUser = newId.Impersonate();

    try
    {
        string cs = @"Server=[myservername];Integrated Security=true";
        using (SqlConnection con = new SqlConnection(cs))
        {
            con.Open();
            SqlTransaction objSqlTran = con.BeginTransaction();

            //string sql = "INSERT INTO fileStreamTest VALUES ((Cast('' As varbinary(Max))),@fName,default); Select fData.PathName() As Path From fileStreamTest Where fId = SCOPE_IDENTITY()";//OUTPUT inserted.fid 
            SqlCommand insertFileCommand = con.CreateCommand();

            insertFileCommand.Transaction = objSqlTran;

            insertFileCommand.CommandText = "INSERT INTO fileStreamTest.dbo.fileStreamTest (RowGuid,fData) VALUES (@FileID,CAST ('' as varbinary(max)))";

            Guid newFileID = Guid.NewGuid();

            insertFileCommand.Parameters.Add("@FileID",SqlDbType.UniqueIdentifier).Value = newFileID;

            insertFileCommand.ExecuteNonQuery();

            SqlCommand getPathAndTokenCommand = con.CreateCommand();

            getPathAndTokenCommand.Transaction = objSqlTran;

            getPathAndTokenCommand.CommandText =
                "SELECT fData.PathName(),GET_FILESTREAM_TRANSACTION_CONTEXT() " +
                "FROM   fileStreamTest.dbo.fileStreamTest " +
                "WHERE  rowGuid = @FileID";

            getPathAndTokenCommand.Parameters.Add("@FileID",SqlDbType.UniqueIdentifier).Value = newFileID;

            SqlDataReader tokenReader = getPathAndTokenCommand.ExecuteReader(CommandBehavior.SingleRow);

            tokenReader.Read();

            SqlString filePathName = tokenReader.GetSqlString(0);

            SqlBinary fileToken = tokenReader.GetSqlBinary(1);

            tokenReader.Close();

            SqlFileStream sqlFile = new SqlFileStream(filePathName.Value,fileToken.Value,System.IO.FileAccess.ReadWrite);
            sqlFile.Close();

            objSqlTran.Rollback();
            //objSqlTran.Commit();
            con.Close();

        }
    }
    finally
    {
        impersonatedUser.Undo();
    }
}
};

但是,当它到达该行：

SqlFileStream sqlFile = new SqlFileStream(filePathName.Value,System.IO.FileAccess.ReadWrite);

我明白了：

执行用户定义的例程或聚合“sp_fileController”期间发生.NET Framework错误：

System.ComponentModel.Win32Exception: The request is not supported
System.ComponentModel.Win32Exception: 
   at System.Data.SqlTypes.SqlFileStream.OpenSqlFileStream(String path,Byte[] transactionContext,FileAccess access,FileOptions options,Int64 allocationSize)
   at System.Data.SqlTypes.SqlFileStream..ctor(String path,FileAccess access)
   at StoredProcedures.sp_fileController(String friendlyName,String filePath)

谁能告诉我如何解决这个问题？只是我不能用sql 2008 Express版本以这种方式执行代码？