SharePoint memory leak

Question

Does this contain a memory leak? I've been trying to better understand memory leaks, but I can't tell if I have corrected this? If not, how do I correctly dispose of the SPweb object and SPSite object?

using (SPWeb oWebsite = new SPSite(webUrl).OpenWeb()) //Open SP Web
{
    SPListCollection collList = oWebsite.Lists; //Open Lists

    foreach (SPList oList in collList)
    //For Each List Execute this
    {
        if (!oList.Hidden)
        //If the list is hidden do this else nothing
        {
            ListSitesDropDownBox.Items.Add(new ListItem(SPEncode.HtmlEncode(oList.Title), SPEncode.HtmlEncode(oList.Title)));
            ViewState["Item" + counter] = SPEncode.HtmlEncode(oList.Title);
            counter++;
        }
    }
}

Answer 1

Yep, it does. You dispose of SPWeb but forget disposing of SPSite.
The right way to do this:

using (var site = new SPSite(webUrl))
using (var web = site.OpenWeb()) {
    // ...
}

Note that this is equivalent to:

using (var site = new SPSite(webUrl)) {
    using (var web = site.OpenWeb()) {
        // ...
    }
}

but I omitted braces for outer using to reduce code nesting. The bracing rules are the same as for if.

A few stylistic remarks:

• Please, don't use Systems Hungarian in C# code. Just list.

• Comments that rephrase the code above don't make any sense. Keep them constructive, i.e. explaining the purpose of the code. Instead of those four comments, you should've written something like that in the beginning:

  // Populate drop-down list with list names and save them in ViewState