Asp.net C# : Get field value from datagrid

[thahi]

Im beginer so pls help me........................
using C#.net

now we created a datagrid.then we make connection also.in a database we created a table student,the student table hav three feild sid,sname,smark.
there is lote of student details there
we bind to datagrid through the Sql adapter only one Field.thats Sid. there is two textbox here. we hav only see sid only.when u click sid the texbox will appear other feild sname and smark.so how to give codes in to grid for the proces.

[thahi]

im using Asp.net C#

now we created a datagrid.then we make connection also.but how to take selected gridvalue.there two textbox .each textbox will comes another feilds.
that from grid selected values's.so pls give me answer

[CyberSoftHari]

Give related topic to your query.
Post what you tried so far.
Topic :
Asp.net C# : Get field value from datagrid.