检测用于创建RegEx的文件名模式

时间:2014-08-22 18:29:05

标签: c# regex

使用字符串定义RegEx时,我想知道是否有办法让我的代码识别目录中包含的文件中的模式。

目标是使用我们的命名约定重命名这些文件,因此我写了一些东西来尝试创建要在RegEx中使用的表达式。

我在这里开始了一些事情,但我认为这不是最好的,而且我不确定如何填写我的RegEx表达式的"{0}"部分。< / p>

    private Regex m_regex;

    public string DirPattern(string path, string[] extensions) {
        string result = null;
        int endPos = 0;
        int resLen = 0;
        int startLen = 0;
        var dir = new DirectoryInfo(path);
        foreach (var file in dir.GetFiles()) {
            if (extensions.Contains(file.Extension)) {
                if (!String.IsNullOrEmpty(result)) {
                    int sL = 0;
                    int fileLen = file.Name.Length;
                    string one = null;
                    for (int i = 0; i < resLen && i < fileLen; i++) {
                        if (result[i] == file.Name[i]) {
                            sL = i + 1;
                            if (String.IsNullOrEmpty(one)) {
                                one = file.Name;
                            } else {
                                break;
                            }
                        }
                    }
                    if (!String.IsNullOrEmpty(one)) {
                        int eP = 0;
                        int oneLen = one.Length;
                        for (int i = fileLen - 1; -1 < i; i--) {
                            if (result[i] == file.Name[i]) {
                                eP = i - 1;
                            } else {
                                break;
                            }
                        }
                        if ((0 < endPos) && (eP == endPos)) {
                            if ((0 < startLen) && (sL == startLen)) {
                                result = one.Substring(0, startLen) + "{0}" + one.Substring(endPos);
                            } else if (0 < sL) {
                                startLen = sL;
                            }
                        } else if (0 < sL) {
                            startLen = sL;
                        }
                    }
                } else {
                    result = file.Name;
                    resLen = result.Length;
                }
            }
        }
        return result;
    }

    public bool GenerateRexEx(string path, string[] extensions) {
        var pattern = DirPattern(path, extensions);
        if (!String.IsNullOrEmpty(pattern)) {
            m_regex = new Regex(pattern);
            return true;
        }
        return false;
    }

以下是一个与我们公司文件最相似的文件列表示例(我不允许发布):

screenshot

更新

目标是获取具有以下名称的文件:

FOLDER_PATTERN_1 + MixedContent + FOLDER_PATTERN_2

并使用我们的格式重命名:

OUR_PATTERN_1 + MixedContent + OUR_PATTERN_2

这样,我们的软件就能更有效地搜索文件。

1 个答案:

答案 0 :(得分:1)

我认为在你的情况下你只需要在前缀模式和后缀模式中找到字符数。然后你可以简单地用你的模式替换一些字符数。我写了一个简单的代码,我测试并运行。你可以激励自己,并使用我认为的相同方法。无论如何,有一些方面可以做到这一点,但我希望它足以回答你的问题。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;

namespace ConsoleApplication1
{
    static class Program
    {
        static void Main()
        {
            var inputFilenames = new string[]
            {
                "mtn_flint501-muxed",
                "mtn_flint502-muxed",
                "mtn_flint503-muxed",
                "mtn_flint504-muxed",
                "mtn_flint505-muxed",
                "mtn_flint506-muxed",
                "mtn_flint507-muxed",
                "mtn_flint508-muxed",
                "mtn_flint509-muxed",
                "mtn_flint510-muxed",
                "mtn_flint511-muxed",
                "mtn_flint512-muxed",
            };
            var replacedFilenames = ReplaceFileNames(inputFilenames);

            for (int i = 0; i < inputFilenames.Length; i++)
            {
                Console.WriteLine("{0} >> {1}", inputFilenames[i], replacedFilenames[i]);
            }
            Console.ReadKey();
        }

        private const string OurPrefixPattern = "Prefix_";
        private const string OurPostfixPattern = "_Postfix";

        /// <summary>
        /// Method which will find the filename's pattern and replace it with our pattern
        /// </summary>
        /// <param name="fileNames"></param>
        /// <returns></returns>
        public static string[] ReplaceFileNames(params string[] fileNames)
        {
            //At first, we will find count of characters, which are same for
            //all filenames as prefix and store it to prefixCount variable and
            //we will find count of characters which are same for all filenames
            //as postfix and store it to postfixCount variable
            var prefixCount = int.MaxValue;
            var postfixCount = int.MaxValue;
            //We will use first filename as the reference one (we will be comparing)
            //all filenames with this one
            var referenceFilename = fileNames[0];
            var reversedReferenceFilename = referenceFilename.ReverseString();
            //Lets find the prefixCount and postfixCount
            foreach (var filename in fileNames)
            {
                if (filename == referenceFilename)
                {
                    continue;
                }
                //Check for prefix count
                var firstDifferenceIndex = referenceFilename.GetFirstDifferentIndexWith(filename);
                if (firstDifferenceIndex < prefixCount)
                {
                    prefixCount = firstDifferenceIndex;
                }
                //For postfix count we will do the same, but with reversed strings
                firstDifferenceIndex = reversedReferenceFilename.GetFirstDifferentIndexWith(filename.ReverseString());
                if (firstDifferenceIndex < postfixCount)
                {
                    postfixCount = firstDifferenceIndex;
                }
            }
            //So now replace given filnames with our prefix and post fix.
            //Our regex determines only how many characters should be replaced
            var prefixRegexToReplace = string.Format("^.{{{0}}}", prefixCount);
            var postfixRegexToReplace = string.Format(".{{{0}}}$", postfixCount);
            var result = new string[fileNames.Length];
            for (int i = 0; i < fileNames.Length; i++)
            {
                //Replace the prefix
                result[i] = Regex.Replace(fileNames[i], prefixRegexToReplace, OurPrefixPattern);
                //Replace the postfix
                result[i] = Regex.Replace(result[i], postfixRegexToReplace, OurPostfixPattern);
            }
            return result;
        }

        /// <summary>
        /// Gets the first index in which the strings has different character
        /// </summary>
        /// <param name="value"></param>
        /// <param name="stringToCompare"></param>
        /// <returns></returns>
        private static int GetFirstDifferentIndexWith(this string value, string stringToCompare)
        {
            return value.Zip(stringToCompare, (c1, c2) => c1 == c2).TakeWhile(b => b).Count();
        }

        /// <summary>
        /// Revers given string
        /// </summary>
        /// <param name="value">String which should be reversed</param>
        /// <returns>Reversed string</returns>
        private static string ReverseString(this string value)
        {
            char[] charArray = value.ToCharArray();
            Array.Reverse(charArray);
            return new string(charArray);
        }
    }
}

控制台输出如下所示

  

mtn_flint501-muxed&gt;&gt; Prefix_01_Postfix

     

mtn_flint502-muxed&gt;&gt; Prefix_02_Postfix

     

mtn_flint503-muxed&gt;&gt; Prefix_03_Postfix

     

mtn_flint504-muxed&gt;&gt; Prefix_04_Postfix

     

mtn_flint505-muxed&gt;&gt; Prefix_05_Postfix

     

mtn_flint506-muxed&gt;&gt; Prefix_06_Postfix

     

mtn_flint507-muxed&gt;&gt; Prefix_07_Postfix

     

mtn_flint508-muxed&gt;&gt; Prefix_08_Postfix

     

mtn_flint509-muxed&gt;&gt; Prefix_09_Postfix

     

mtn_flint510-muxed&gt;&gt; Prefix_10_Postfix

     

mtn_flint511-muxed&gt;&gt; Prefix_11_Postfix

     

mtn_flint512-muxed&gt;&gt; Prefix_12_Postfix