Java Script Question

Hi
I am looking for a solution to a Java Script question. My question is this, I have a gridview, and in this gridview I have a column, which I use as a flag. The gridview itself is dynamically added to a user control and then to the page. What I would like to do is to use Java Script to hide this column, but I do not know how to do this. Unfortunately, I cannot use code behind, because of the gridview being dynamically added.
Also, I have one further question, I already have some Java Script code that can hide some of the rows based upon the values in my column when a button is clicked. What I want to do is when the page is loaded for the first time, to hide some of these rows, and to use the button in reverse to reveal them again. How do I achieve this?
Thanks

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