Pointer to a buffer to be updated with the contents of the file's preamble.
Value that represents the length of the file's preamble, in bytes. The maximum size of a preamble is 128 bytes.
To set the file's preamble, call the DicomDataSet.SetPreamble(Byte, int, int) method. If the value specified by length is >= 128, then the buffer will be updated with the entire preamble. If length is < 128, then the buffer will be updated with a truncated version of the preamble with length length.