Text Capture using C#.NET

Hi sir,
 
    I have another application,that application i have one grid view that gridview values are continuosly changing fraction of seconds..
Using my application i want to capture that changing text in my rich textbox..
 
How to perform that text capture..I need your help.I waiting for your reply ASAP.Thanks for reply
 
With Regards,
Saravanan
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