How to retrieve data from a gridview by clicking a row on it?

Hello everyone,

Could anyone help me with this problem?

I have a search form named SearchPage.aspx with many fields, one of them is Client. This is a textbox for user enter the Client Code. If the users do not remember exactly the client code they can click on the magnify glass icon beside the textbox and a popup window appears. Then the user enter the client code to the textbox in the popup windows and click Search button. After that, the user chooses one record from the result by clicking on it and the client code and name will fill back to the SearchPage.aspx. I've tried to use an aspx page as a popup and a girdview to display data of Client but i cannot get the data from the grid when clicking on the record. So could anyone tell me how to retrieve data of a row on a gridview just by clicking on it (without checkbox or radio button).

Thank you very  much

 
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