临时保存

 if (!string.IsNullOrEmpty(preProject.ProductLine))
                {
                    var productLineCategory = new ProductLineCategory();
                    var middleProductinterface = productLineCategory.GetProductInterface(preProject.ProductLine, 2, 2);
                    if (middleProductinterface != null)
                    {
                        this.ltl产品线中类.Text = middleProductinterface.Name;
                        if (middleProductinterface != null)
                        {
                            var bigProductinterface = productLineCategory.GetProductInterface(middleProductinterface.Name, 2, 1);
                            if (bigProductinterface != null)
                            {
                                this.ltl产品线大类.Text = bigProductinterface.Name;
                            }
                        }
                    }
                }