求教各位，这样要这么判断！！！
有一个txt文件，里面存储这多行的数字，比如：
000000000000111010010101010000000000000000
111010101000111100000000000000000110010000
000010101010101010010000000000000000000000
100001010100101000000000110000000010001001
110010101010000000000000000000000000000000
按64个字符算成一组， 输出每组中字符为1的下标。 这个下标是每组内的下标，即0-63且衔接也已经完成，现在我要输出的格式中加入判断，就是碰到每组第一个1的时候输出start，最后一个1的时候输出end，如下所示：
.......
M[8] start X[8] P[8]
M[11] P[8] X[11] P[11]
M[12] P[11] X[12] P[12]
......
M[45] P[40] X[45] end
这样要这么解决？
[解决办法]
var lines = File.ReadAllLines(@"E:\我的项目文档\c.txt");var sw = new StreamWriter(@"E:\我的项目文档\De.txt", false);var blen = 64;foreach (var item in lines){ string[] blks; var count = item.Length / blen; var rem = item.Length % blen; if (rem > 0) { blks = new string[count + 1]; blks[count] = item.Substring(blen * count, rem); } else { blks = new string[count]; } for (int i = 0; i < count; i++) { blks[i] = item.Substring(blen * i, blen); } for (int i = 0; i < blks.Length; i++) { var str = blks[i]; var idxs = new List<int>(blen); var index = -1; while ((index = item.IndexOf('1', index + 1)) >= 0) { idxs.Add(index); } var istr = i.ToString(); var sidxstr = idxs[0].ToString(); sw.WriteLine(string.Concat("M", istr, "[", sidxstr, "] O[", istr, "] X[", sidxstr, "] P", istr, "[", sidxstr, "]")); var lidx = idxs.Count - 1; for (int j = 1; j < lidx; j++) { var idxstr = idxs[j].ToString(); sw.WriteLine(string.Concat("M", istr, "[", idxstr, "] P", istr, "[", sidxstr, "] X[", idxstr, "] P", istr, "[", idxstr, "]")); sidxstr = idxstr; } var eidxstr = idxs[lidx].ToString(); sw.WriteLine(string.Concat("M", istr, "[", eidxstr, "] P", istr, "[", sidxstr, "] X[", eidxstr, "] I[", istr, "]")); sw.Flush(); }}