how to get dropdownlist selected value with "PreviousPage.FindControl" ?

hi,

i post my dropdownlist value to another web page which name is "marka".

i couldnt get value. i got an error. "Object reference not set to an instance of an object."
codes are ;

Dim markadrop As DropDownList = PreviousPage.FindControl("marka")
Label1.Text = markadrop.SelectedValue



 

thanks

mustafa
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