Toggle DIV visibility with a button

Hello,

 I am using Visual Web Developer 2008 to create a site in C# and ASP.NET.

I have 5 gridviews that pull information from my database.  I would like to show them initially, and then hide them if the user clicks the "-" sign next to it.  If he/she clicks the "-", the gridview will disappear, and the "-" sign next to it becomes a "+" sign.  Can someone help me with what code I need for the page, as well as for the code behind?

 Thanks!
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