hi all i am interested to make a program that will read the data from webpage using client.read() but i want to put the main webpage with much better design on SD card and access it after the login screen. what i want is to save the RAM and the ROM by making a small code for only checking login and then the main page from SD.
2ndly i want to refresh a block or webpage to automatically refresh and display a variable's value which is changing every second. But i am not interested in Auto refreshing the entire page.
any ideas or ref material on this topic ??? i will be greatful and thnx in advance 
hi all i am interested to make a program that will read the data from webpage using client.read() but i want to put the main webpage with much better design on SD card and access it after the login screen.
You can't READ a web page.
Is your Arduino supposed to be a server? That is the only situation where reading from an SD card makes sense. If that is the case, the server sends an HTML file to the client (browser).
what i want is to save the RAM and the ROM by making a small code for only checking login and then the main page from SD.
You can save RAM or ROM, not both.
What is your problem with serving HTML data from an SD card?
Yes i am making a web server to control traffic lights and adjust the timings . i wanted to have a block on the page which will be showing the count down timer . i managed to make that but the real problem is to update that time every second without refreshing the whole page. m new on the web stuff and not sure that client.read() will read the data from webpage that i will make from dream viewer and save it on sd card as making an interactive webpage by using the client.pritnln() takes lots of RAM and is very hectic .
m new on the web stuff and not sure that client.read() will read the data from webpage that i will make from dream viewer and save it on sd card
Of course it won't. You'll need to use SD::read() to read from the SD card, and client.print() to send to the client.
making an interactive webpage by using the client.pritnln() takes lots of RAM and is very hectic
Using the F() macro will help reduce the amount of SRAM used.
If you are planning to use DreamWeaver to design the web page, it isn't going to be anything but a static page. That static page can be stored in flash memory, without using any SRAM at all.
The whole idea, though, is to serve up dynamic pages, where the content is NOT the same every time the page is served. That can still be done with mostly static snippets stored in flash, with the dynamic part being choosing the right static snippets to include in the served page.
You should look into using frames, and serving up the input stuff in one frame, refreshed only as the user interacts with it, and one frame that is refreshed automatically (using Meta tags) every second. That frame should be very small, and relatively quick to serve up.