Remove Webpart from gallery

This is how you would programmatically remove a webpart from a webpart gallery in the feature event receiver.

public override void FeatureDeactivating(SPFeatureReceiverProperties properties)

{

    using (SPWeb currentWeb = ((SPSite)properties.Feature.Parent).RootWeb)

    {

        //remove Student lottery webpart from web part gallery

        SPList webPartList = currentWeb.Lists["Web Part Gallery"];

        foreach (SPListItem webpart in webPartList.Items)

        {

            if (webpart["Title"].ToString() == "WebpartTitle")

            {

                webPartList.Items.DeleteItemById(webpart.ID);

                break;

            }

        }

        webPartList.Update();

        currentWeb.Update();

    }

}

You can find the webpart title in the mywebpartRegistration.webpart file, look for an element property with an name attribute of title.