E2739158012008-10-01O9918107NPF7547379999010012008-10-0100125000000
E2739158PU0000-00-00 010012008-10-0100081625219
E3180826011985-01-14L9918007NPM4927359999010011985-01-1400005620000
E3180826PU0000-00-00 020011985-01-14000110443500021997-01-1400000518799
E3292015011985-01-16L9918007NPM4927349999010011985-01-1600003623300
我有这个平面文件，我需要根据第2位到第8位将其分组example（2739158/3180826/3292015）并写入另一个平面文件。因此，以“ E”开头的数据应与该组字段一起在单行中重复（起始位置为第2至第8位），我应在“ E”之后占据第9位。
此外，我还需要用（'*'星号）替换空白空间例如
第一行
2739158**E**012008-10-01O9918107NPF7547379999010012008-10-0100125000000*****E**012008-10-01O9918107NPF7547379999010012008-10-0100125000000
第二行
3180826**E**011985-01-14L9918007NPM4927359999010011985-01-1400005620000**E**011985-01-14L9918007NPM4927359999010011985-01-140000562000**E**011985-01-14L9918007NPM4927359999010011985-01-140000562000***
第三行
3292015**E**011985-01-16L9918007NPM4927349999010011985-01-1600003623300****
我们可以在Stream reader c＃中做到这一点吗？任何帮助将不胜感激。文件大小超过285 MB，因此最好通过Stream Reader进行阅读？谢谢
@@ jdweng：非常感谢您的输入。我以某种方式尝试了而不进行分组，它按预期工作。感谢尝试解决此问题的每个人。
string sTest= string.Empty; List<SortLines> lines = new List<SortLines>();
List<String> FinalLines = new List<String>();
using (StreamReader sr = new StreamReader(@"C:\data\Input1.txt))
{
sr.ReadLine();
string line = "";
while (!sr.EndOfStream)
{
line = sr.ReadLine();
//line = line.Trim();
if (line.Length > 0)
{
line = line.Replace(" ", "*");
SortLines newLine = new SortLines()
{
key = line.Substring(1, 7),
line = line
};
if (sTest != newLine.key)
{
//Add the Line Items to String List
sOuterLine = sTest + sOneLine;
FinalLines.Add(sOuterLine);
string sFinalLine = newLine.line.Remove(1, 7);
string snewLine = newLine.key + sFinalLine;
sTest = snewLine.Substring(0, 7);
//To hold the data for the 1st occurence
sOtherLine = snewLine.Remove(0, 7);
bOtherLine = true;
string sKey = newLine.key;
lines.Add(newLine);
}
else if (sTest == newLine.key)
{
string sConcatLine = String.Empty;
string sFinalLine = newLine.line.Remove(1, 7);
//Check if 1st Set
if (bOtherLine == true)
{
sOneLine = sOtherLine + sFinalLine;
bOtherLine = false;
}
//If not add subsequent data
else
{
sOneLine = sOneLine + sFinalLine;
}
//Check for the last line in the flat file
if (sr.Peek() == -1)
{
sOuterLine = sTest + sOneLine;
FinalLines.Add(sOuterLine);
}
}
}
}
}
//Remove the Empty List
FinalLines.RemoveAll(x => x == "");
StreamWriter srWriter = new StreamWriter(@"C:\data\test.txt);
foreach (var group in FinalLines)
{
srWriter.WriteLine(group);
}
srWriter.Flush();
srWriter.Close();
尝试下面的代码：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
namespace ConsoleApplication1
{
class Program
{
const string INPUT_FILENAME = @"c:\temp\test.txt";
const string OUTPUT_FILENAME = @"c:\temp\test1.txt";
static void Main(string[] args)
{
List<SortLines> lines = new List<SortLines>();
StreamReader reader = new StreamReader(INPUT_FILENAME);
string line = "";
while ((line = reader.ReadLine()) != null)
{
line = line.Trim();
if (line.Length > 0)
{
line = line.Replace(" ", "*");
SortLines newLine = new SortLines() { key = line.Substring(2, 7), line = line };
lines.Add(newLine);
}
}
reader.Close();
var groups = lines.GroupBy(x => x.key);
StreamWriter writer = new StreamWriter(OUTPUT_FILENAME);
foreach (var group in groups)
{
foreach (SortLines sortLine in group)
{
writer.WriteLine(sortLine.line);
}
}
writer.Flush();
writer.Close();
}
}
public class SortLines : IComparable<SortLines>
{
public string line { get; set; }
public string key { get; set; }
public int CompareTo(SortLines other)
{
return key.CompareTo(other);
}
}
}