how to check if a webpart already exists on a page or not

Question

I am adding three webparts with different titles to a given page url, but I need to check if webpart is already on page or not, here is the code i am using atm to add webpart to the page.

     using (SPSite mySite = new SPSite(PageUrl))
                {
                    using (SPWeb web = mySite.OpenWeb())
                    {
                        try
                        {
                            web.AllowUnsafeUpdates = true;

                            using (SPLimitedWebPartManager manager = web.GetLimitedWebPartManager("default.aspx", PersonalizationScope.Shared))
                            {
                            webpart webpart = new webpart();
                            webpart.AllowClose = true;
                            webpart.AllowMinimize = true;
                            webpart.AllowConnect = true;
                            webpart.ChromeType = PartChromeType.None;
                            webpart.ChromeState = PartChromeState.Normal;
                            webpart.AllowZoneChange = true;
                            webpart.AllowHide = true;
                            webpart.ExportMode = WebPartExportMode.All;
                            webpart.Hidden = false;
                            webpart.AllowEdit = true;
                            webpart.AllowZoneChange = true;
                            webpart.AllowHide = true;
                            webpart.ButtonCSSClass = "DefaultButton";

                            manager.AddWebPart(webpart, "Right", index);
                            }
                      }
                 }

Answer 1

Here is LINQ code that finds a Web Part with a title:

    string _webPartTitle = "mywebpart";
    //Retrive the webpart with some title
    IList<Microsoft.SharePoint.WebPartPages.WebPart> _listFormWebParts = (from _wp in manager.WebParts.Cast<Microsoft.SharePoint.WebPartPages.WebPart>()
                                                                            where string.Compare( _wp.Title , _webPartTitle  , true ) == 0
                                                                            select _wp).ToList();

    //Check if there are any web parts found
    if (_listFormWebParts != null)
    {

    }