比较文本文件的字符串

Question

我有三个文本文件：file1、file2 和 file3，它们都包含电子邮件。文件 1 应该包含所有电子邮件，文件 2 包含所有 A-M 电子邮件，文件 3 包含来自 n-z 的电子邮件（这并不重要，但我认为它有助于提供一些上下文。）

我正在用 c# 编写一个控制台应用程序，它将查看这三个文件，如果有一封电子邮件不是 1 而不是它应该在的位置，那么它将写入一个主文件，说明需要什么要添加到什么。

例如，假设我有电子邮件 john@example.com。如果在file1中找到但在file2中找不到，则masterfile的输出需要为"this email needs to be added to file2: john@example.com"。现在，如果它被反转，并且在 file2 中找到了电子邮件，但在 file1 中找不到，那么输出应该是 "this email needs to be added to file1: john@example.com"

作为我的代码的一部分，我正在寻找的答案需要在某种 foreach 循环和 if 语句中，但是我有点迷失了我需要输入的内容。如果有人可以帮助我在弄清楚我必须在我的陈述中使用它是什么时，我将非常感激。如果有人对此有任何疑问，请随时提问！

//Making a list for file1
List<string> listFullPack = new List<string>();
string line;
StreamReader sr = new StreamReader("file1");
while ((line = sr.ReadLine()) != null)
{
    listFile1.Add(line);
}
sr.Close();

//Making a list for file2
List<string> listDen1 = new List<string>();
string line1;

StreamReader sr1 = new StreamReader("file2");
while ((line1 = sr1.ReadLine()) != null)
{
    listFile2.Add(line1);
}
sr1.Close();

//Making a list for file3
List<string> listDen2 = new List<string>();
string line2;

StreamReader sr2 = new StreamReader("file3");
while ((line2 = sr2.ReadLine()) != null)
{
    listFile3.Add(line2);
}
sr2.Close();

//This will double check that emails are in
foreach (string element in listFullPack)
{
    System.Console.WriteLine(element);
    Debug.WriteLine(element);

    if (element == "jimbob@example.com")
    {

        Debugger.Break();
    }
}

//this will compare the file1 list to the file2 list
var firstNotSecond = listFile1.Except(listFile2).ToList();
var secondNotFirst = listFile2.Except(listFile1).ToList();

//this will compare the file2 list to the file3 list
var firstNotThird = listFile1.Except(listFile3).ToList();
var thirdNotFirst = listFile3.Except(listFile1).ToList();

//this will compare the file2 list to the file3 list
var secondNotThird = listFile2.Except(listFile3).ToList();
var thirdNotSecond = listFile3.Except(listFile2).ToList();

foreach (string element in listFile1) // This is where I am lost
{
    if (!)
    {

    }
}

Answer 1

您可以尝试这样简单的操作：

    //Making a list for file1
    HashSet<string> listFile1 = new HashSet<string>();
    string line;
    StreamReader sr = new StreamReader("file1");
    while ((line = sr.ReadLine()) != null)
    {
        listFile1.Add(line);
    }
    sr.Close();

    //Making a list for file2
    HashSet<string> listFile2 = new HashSet<string>();
    string line1;
    StreamReader sr1 = new StreamReader("file2");
    while ((line1 = sr1.ReadLine()) != null)
    {
        listFile2.Add(line1);
    }
    sr1.Close();

    //Making a list for file3
    HashSet<string> listFile3 = new HashSet<string>();
    string line2;
    StreamReader sr2 = new StreamReader("file3");
    while ((line2 = sr2.ReadLine()) != null)
    {
        listFile3.Add(line2);
    }
    sr2.Close();

    IEnumerable<string> allEmails = listFile1.Union(listFile2).Union(listFile3);

    // this will double check the emails
    foreach (string element in allEmails)
    {
        if (!listFile1.Contains(element))
            System.Console.WriteLine("file 1 is missing " + element);

        int firstCharAscii = element.Trim().ToLower()[0];
        if (firstCharAscii < 110)
        {
            // less than "n"
            if (!listFile2.Contains(element))
                System.Console.WriteLine("file 2 is missing " + element);
            if (listFile3.Contains(element))
                System.Console.WriteLine("file 3 erroneously contains " + element);
        }
        else
        {
            // "n" or greater
            if (!listFile3.Contains(element))
                System.Console.WriteLine("file 3 is missing " + element);
            if (listFile2.Contains(element))
                System.Console.WriteLine("file 2 erroneously contains " + element);
        }
    }

请记住，随着电子邮件数量的增加，List<string>.Contains() 方法成为确定存在或不存在的低效方法。你会更适合 HashSet<string> class。此外，如果出于某种原因您正在阅读 Unicode 字符串，您将需要一种更强大的方法来检查第一个字符的值。

Answer 2

List<string> fullList = File.ReadAllLines("fullist.txt").ToList<string>();
List<string> firstList = File.ReadAllLines("list1.txt").ToList<string>();
List<string> secondList = File.ReadAllLines("list2.txt").ToList<string>();

firstList.ForEach(m => {if (!fullList.Contains(m)/*Or other logic*/) {fullList.Add(m+" from 1 Needs to be in master");}});
secondList.ForEach(m => {if (!fullList.Contains(m)/*Or other logic*/) {fullList.Add(m+ " from 2 Needs to be in master");}});

Answer 3

这应该可以为您完成。

        List<string> file1Parsed = new List<string>();
        List<string> file2Parsed = new List<string>();
        List<string> file3Parsed = new List<string>();

        using (StreamReader readerFile1 = new StreamReader(@"c:\file1.txt"))
        {
            while (!readerFile1.EndOfStream)
            {
                file1Parsed.Add(readerFile1.ReadLine());
            }
        }

        using (StreamReader readerFile2 = new StreamReader(@"c:\file2.txt"))
        {
            while (!readerFile2.EndOfStream)
            {
                file2Parsed.Add(readerFile2.ReadLine());
            }
        }

        using (StreamReader readerFile3 = new StreamReader(@"c:\file3.txt"))
        {
            while (!readerFile3.EndOfStream)
            {
                file3Parsed.Add(readerFile3.ReadLine());
            }
        }

        char[] firstSet = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M' };
        char[] secondSet = { 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z' };

        var file1InFile2 = file1Parsed.Where(y => y.ToUpper().IndexOfAny(firstSet) == 0).Select(x => x);
        var file1InFile3 = file1Parsed.Where(y => y.ToUpper().IndexOfAny(secondSet) == 0).Select(x => x);

        using (StreamWriter writer = new StreamWriter(@"C:\notExists.txt"))
        {
            file1InFile2.Where(x => !file2Parsed.Contains(x.Trim())).ToList().ForEach(y => writer.WriteLine("This email needs to be added to file2: " + y));
            file1InFile3.Where(x => !file3Parsed.Contains(x.Trim())).ToList().ForEach(y => writer.WriteLine("This email needs to be added to file3: " + y));
            file2Parsed.Where(x => !file1InFile2.Contains(x.Trim())).ToList().ForEach(y => writer.WriteLine("This email needs to be added to file1: " + y));
            file3Parsed.Where(x => !file1InFile3.Contains(x.Trim())).ToList().ForEach(y => writer.WriteLine("This email needs to be added to file1: " + y));
        }

我修改了它以减少代码

比较文本文件的字符串

Comparing strings of text files

c#

foreach

file-io

loops

if-statement