Unable to access the a value attribute data in a context node???

Hello Gurus,

   I have a model node and in that a value attribute is there. i am able to fill the value attribute with data and even display in the webui. Consider In webui if the attribute value is been changed and i need that changed value  in my code.. How can i fetch the data in the value attribute here??

Thanks in Advance,

   Durga Prasad.