.NET字串起訖計算

例如有一dataset中的某一字串為6A0001,6A0002,6A0003,6A0007,6B0001,6B0002...代表箱號.若需要顯示為6A0001~6A0003;6A0007;6B0001~6B0002,代碼如下

    /// <summary>
        /// 从字符串中的结尾取得指定长度无符号数字。
        /// </summary>
        /// <param name="text">The text.</param>
        /// <param name="length">要取得数字的位数，如果为0则表示不知道位数将取得结尾的所有数字部分，在匹配成功后会将
        /// 此变量置为实际取得的数字。</param>
        /// <param name="prefixText">存放除去取出数字后字符串的变量。</param>
        /// <param name="number">存放结果数字。</param>
        /// <example>
        /// string s = "MB2A100105";<br/>
        /// string s1;<br/>
        /// ulong l;<br/>
        /// GetNumberOfTextEnd(s, 0, out s1, out l); //l=100005<br/>
        /// GetNumberOftestEnd(s, 6, out s1, out l); //l=100005<br/>
        /// GetNumberOfTextEnd(s, 3, out s1, out l); //l=105<br/>
        /// </example>
        /// <returns></returns>
        public static void GetNumberOfTextEnd(string text, ref int length, out string prefixText, out ulong number)
        {
            string expresssion = @"[0-9]{{{0}}}$";
            if (length <= 0)
            ...{
                expresssion = string.Format(expresssion, "0,");
            }
            else
            ...{
                expresssion = string.Format(expresssion, length);
            }

            Match match = Regex.Match(text, expresssion, RegexOptions.RightToLeft);
            if (match.Success)
            ...{
                number = ulong.Parse(match.Value);
                prefixText = text.Substring(0, match.Index);
                length = match.Length;
            }
            else
            ...{
                throw new HanRocException("NFW-0025", text); //无法在文本结尾找到数字。
            }
        }

if (ds.Tables[0].Rows.Count>0)
            ...{
                boxQty = ds.Tables[0].Rows.Count;
                string currentBox = ds.Tables[0].Rows[0]["OUTER_BOX"].ToString();
                int length = -1;
                ulong beginNum, endNum;
                string prefixText1 = "", prefixText2 = "", nextBox = "";
                boxRange = currentBox;

                for (int i = 1; i < ds.Tables[0].Rows.Count; i++)
                ...{
                    length = 0;
                    Helper.GetNumberOfTextEnd(currentBox, ref length, out prefixText1, out beginNum);
                    nextBox = ds.Tables[0].Rows[i]["OUTER_BOX"].ToString();
                    length = 0;
                    Helper.GetNumberOfTextEnd(nextBox, ref length, out prefixText2, out endNum);
                    if (prefixText1 != prefixText2)
                    ...{
                        boxRange += " ; " + nextBox;
                        currentBox = nextBox;
                    }
                    else
                    ...{
                        if (beginNum + 1 == endNum)
                        ...{
                            if (i == ds.Tables[0].Rows.Count - 1)
                            ...{
                                boxRange += " ~ " + nextBox;
                                continue;
                            }
                            else
                            ...{
                                string box = "", prefix = "";
                                ulong num;
                                length = 0;
                                box = ds.Tables[0].Rows[i + 1]["OUTER_BOX"].ToString();
                                Helper.GetNumberOfTextEnd(box, ref length, out prefix, out num);
                                if (prefix != prefixText2)
                                ...{
                                    boxRange += " ~ " + nextBox;
                                    currentBox = nextBox;
                                }
                                else
                                ...{
                                    if (endNum + 1 < num)
                                    ...{
                                        boxRange += " ~ " + nextBox;
                                        currentBox = nextBox;
                                    }
                                    else
                                    ...{
                                        currentBox = nextBox;
                                        continue;
                                    }
                                }
                            }
                        }
                        else if (beginNum + 1 < endNum)
                        ...{
                            boxRange += " ; " + nextBox;
                            currentBox = nextBox;
                        }
                        else
                        ...{
                            currentBox = nextBox;
                            continue;
                        }
                    }
                }
            }