public void FileCopy(string source, string target)
{
using (FileStream fileRead = new FileStream(source, FileMode.Open, FileAccess.Read,FileShare.ReadWrite))
{
byte[] bb = new byte[1024 * 1024 * 5];
int r = fileRead.Read(bb, 0, bb.Length);
using (FileStream fileWrite = new FileStream(target, FileMode.Create, FileAccess.Write))
{
while (r > 0)
{
fileWrite.Write(bb, 0, r);
r = fileRead.Read(bb, 0, bb.Length);
}
fileWrite.Close();
}
fileRead.Close();
}
}

此方式通用