c# - How to programmatically set a custom icon on an Outlook search folder? (i.e. Outlook Folder SetCustomIcon) -

i attempting use folder.setcustomicon() method place custom icon on saved search folder programmatically created. setcustomicon() documentation sparse can found here reference.

also, object expects here , again examples sparse.

would know how set custom icon folder? following code have far:

searchfolders = inboxfolder.store.getsearchfolders(); foreach (outlook.folder folder in searchfolders) {     if (folder.name == "expiring retention policy mail")     {         folder.showitemcount = microsoft.office.interop.outlook.olshowitemcount.olshowtotalitemcount;         folder.setcustomicon(new bitmap(32, 32));   // <=-- isn't working because it's expecting stdpicture has sparse information on how convert type.         globals.thisaddin.application.activeexplorer().currentfolder = folder;       } } 

you need use picturedispconverter go image/icon ipicturedisp. below example msdn. works in outlook 2010+. view custom folder icons in outlook 2013, need view folder list - not mail view.

setcustomicon mapifolder

private static void setcustomicon(outlook.mapifolder folder) {     icon icon = null;     try     {         icon = properties.resources.mycustomicon_16x16;         stdole.stdpicture iconpicturedisp = picturedispconverter.toipicturedisp(icon) stdole.stdpicture;         folder.setcustomicon(iconpicturedisp);     }         {         icon.dispose();     } } 

picturedispconverter (icon->ipicturedisp, image->ipicturedisp)

public static class picturedispconverter {     //ipicturedisp guid.      public static guid ipicturedispguid = typeof(stdole.ipicturedisp).guid;      // converts icon ipicturedisp.      public static stdole.ipicturedisp toipicturedisp(icon icon)     {         pictdesc.icon picticon = new pictdesc.icon(icon);         return picturedispconverter.olecreatepictureindirect(picticon, ref ipicturedispguid, true);     }      // converts image ipicturedisp.      public static stdole.ipicturedisp toipicturedisp(image image)     {         bitmap bitmap = (image bitmap) ? (bitmap)image : new bitmap(image);         pictdesc.bitmap pictbit = new pictdesc.bitmap(bitmap);         return picturedispconverter.olecreatepictureindirect(pictbit, ref ipicturedispguid, true);     }       [dllimport("oleaut32.dll", entrypoint = "olecreatepictureindirect", exactspelling = true,     preservesig = false)]     private static extern stdole.ipicturedisp olecreatepictureindirect(     [marshalas(unmanagedtype.asany)] object picdesc, ref guid iid, bool fown);      private readonly static handlecollector handlecollector =     new handlecollector("icon handles", 1000);      // winforms comment:      // pictdesc union in native, we'll      // define different ones different types      // "unused" fields there make right      // size, since struct in native big biggest      // union.      private static class pictdesc     {         //picture types          public const short pictype_uninitialized = -1;         public const short pictype_none = 0;         public const short pictype_bitmap = 1;         public const short pictype_metafile = 2;         public const short pictype_icon = 3;         public const short pictype_enhmetafile = 4;          [structlayout(layoutkind.sequential)]         public class icon         {             internal int cbsizeofstruct = marshal.sizeof(typeof(pictdesc.icon));             internal int pictype = pictdesc.pictype_icon;             internal intptr hicon = intptr.zero;             internal int unused1 = 0;             internal int unused2 = 0;              internal icon(system.drawing.icon icon)             {                 this.hicon = icon.tobitmap().gethicon();             }         }          [structlayout(layoutkind.sequential)]         public class bitmap         {             internal int cbsizeofstruct = marshal.sizeof(typeof(pictdesc.bitmap));             internal int pictype = pictdesc.pictype_bitmap;             internal intptr hbitmap = intptr.zero;             internal intptr hpal = intptr.zero;             internal int unused = 0;             internal bitmap(system.drawing.bitmap bitmap)             {                 this.hbitmap = bitmap.gethbitmap();             }         }     } }