How achieve history.back() effect in the asp.net code itself ?

Dear All,

             I have a HTML table and some text box inside that table too. So once I submit it will send the page and I will check the contents of the text box and if all is correct I will take them to the next level else I want to go back to the page before it was submit some thing like history.back() ? So my logic is if (marks correct) next level else go back to previous so that they can make changes ? How can I achieve this effect? Thanks.
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