Undo and Redo function.....

I want to use the "undo" and "redo" functionality in my html page using javascript funciton. how can i acheive this one ? plz anyone help me.

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suresh

hi friends,

i got the code for the above problem..

Undo - document.execCommand('undo',false,null);
Redo - document.execCommand('redo',false,null);

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suresh