>I have a table with a field called tablename which contains name of table that I have I want to scan the table and open all the tables for example
>use &tablename
>and I m getting a error &tablename does not exist
>can anyone help me how to do such a thing

Sergey's example is good. I would only add a check to see if the file exists.
I don't know if you can always assume the file indicated in your tablename field really exists on disk (or even that it is in the path).

if file(lctablename + ".dbf")
  * do the processing as Sergey indicated
else
  * file not found
endif