delphi - XE6 - How to convert TStringStream content to TStream? -

i using following code convert tstringstream tstream. give error when try copy tstringstream's content tstream.

it seems making obvious mistake not able catch it.

my code:

procedure tfrmmain2.button1click(sender: tobject); var   ss:tstringstream;   s, s2:tstream;   photostr: string; begin   photostr := 'hello world, testing: /9j/4aaqskzjrgabaqaaaqabaad//' +      'ga7q1jfqvrpujogz2qtanblzyb2ms4wich1c2luzybjskcgslbfryb2njip' +      'lcbxdwfsaxr5id0goduk/9saqwafawqebamfbaqebqufbgcmcachbwcpcwsj' +      'dbepehirdxerexycfxmughurerghgbodhr8fhxmxiiqihiqchh8e';    ss := tstringstream.create(photostr);   s := tstream.create();   s.copyfrom(ss, ss.size);  //<= line gives error end; 

the error message getting is: ...class ewriteerror message 'stream write error'.

i don't know why getting error.

you creating instance of tstream abstract class. must never instantiate tstream directly. instantiate descendent class instead, such tfilestream, tmemorystream, etc.