private string MakeAvailableServiceText(string ext, long fileSize)
{
var text = string.Join(", ",
ImageServiceCombo.Items.Cast<string>()
.Where(serviceName =>
!string.IsNullOrEmpty(serviceName) &&
this.pictureService[serviceName].CheckFileExtension(ext) &&
this.pictureService[serviceName].CheckFileSize(ext, fileSize)));
if (string.IsNullOrEmpty(text))
return Properties.Resources.PostPictureWarn6;
return text;
}