Thanks for reply Mudassar Ahamed Khan. I forgot to post major thing. value should be retrieved and displayed from database table
Eg.
I have three column in my table
City companyName area
Chennai Reliance AnnaNagar
Coimbatore ChennaiSilk Townhall
Coimbatore PothysSilk Gandhipuram
so if i type coimbatore in onetexbox area name should be displayed in another textbox without refreshing the page by textchanged event in javscript
I have done it on sever side in asp.net.