水印字体格式实现不了啥原因？？

水印字体格式按以下设置实现不了啥原因？？
System.Drawing.FontStyle type1 = new FontStyle();                switch (type)
                {
                    case "普通":
                        type1 = FontStyle.Regular;
                        break;
                    case "粗体":
                        type1 = FontStyle.Bold;
                        break;
                    default:                        break;
                }
                 System.Drawing.FontStyle type3=new FontStyle();
                switch (type2)
                {
                    case "普通":
                        type3= FontStyle.Regular;
                        break;
                    case "粗体":
                        type3 = FontStyle.Bold;
                        break;
                    default:
                        
                        break;
                }
                System.Drawing.FontStyle Italic1 = new FontStyle();
                switch (Italic)
                {
                    case "普通":
                        Italic1 = FontStyle.Regular;
                        break;
                    case "斜体":
                        Italic1 = FontStyle.Italic;
                        break;
                    default:
                        
                        break;
                }
                System.Drawing.FontStyle Italic3=new FontStyle();
                switch (Italic2)
                {
                    case "普通":
                        Italic3 = FontStyle.Regular;
                        break;
                    case "斜体":
                        Italic3 = FontStyle.Italic;
                        break;
                    default:
                        
                        break;
                }                //System.Drawing.FontStyle type1 = FontStyle.Bold;
                System.Drawing.Font font = new System.Drawing.Font(txtfont, float.Parse(txtsize),type1|Italic1);
                System.Drawing.Font font2 = new System.Drawing.Font(txtfont2, float.Parse(txtsize2),type3|Italic3);