Open a file and replace strings in C#

Question

I\'m trying to figure out the best way to open an existing file and replace all strings that match a declared string with a new string, save it then close.

Suggestio

Answer 1

public partial class ReadAndChange : System.Web.UI.Page
{
    ArrayList FolderList = new ArrayList();
    ArrayList FolderListSearch = new ArrayList();
    ArrayList FileList = new ArrayList();
    protected void Page_Load(object sender, EventArgs e)
    {
        AllFolderList("D:\\BinodBackup\\Nilesh\\14.5.2013\\Source");
        foreach (string Path in FolderList)
        {
            AllFileList(Path);
        }
        foreach (string Path in FileList)
        {
            ReplaceFile(Path, Path.Replace("Source", "EditedCode"));
        }

        //string SourcePath = "D:\\BinodBackup\\Nilesh\\14.5.2013\\Onesource\\Onesource\\UserManagement\\UserControls\\AddUserDetails.ascx.cs";
        //string ReplacePath = "D:\\AddUserDetails.ascx.cs";
        //ReplaceFile(SourcePath, ReplacePath);
    }

    private static void ReplaceFile(string SourcePath, string ReplacePath)
    {
        int counter = 1;
        string line;

        // Read the file and display it line by line.
        System.IO.StreamReader file = new System.IO.StreamReader(SourcePath);
        while ((line = file.ReadLine()) != null)
        {
            if (!(line.Contains("//")))
            {
                if (line.Contains(".LogException("))
                {
                    //Console.WriteLine(counter.ToString() + ": " + line);
                    string[] arr = line.Split(',');
                    string stringToReplace = arr[0].Replace("LogException", "Publish") + " , " + arr[2].Trim() + " , " + arr[3].Replace(");", "").Trim() + " , " + arr[1].Trim() + ");";
                    //File.WriteAllText(currentPath, Regex.Replace(File.ReadAllText(currentPath), line, line + " Added"));
                    File.WriteAllText(ReplacePath, File.ReadAllText(ReplacePath).Replace(line, stringToReplace));
                    //ReplaceInFile(currentPath, line, stringToReplace);
                }
            }

            counter++;
        }

        file.Close();
    }
    private void AllFileList(string FolderPath)
    {
        DirectoryInfo dir = new DirectoryInfo(FolderPath);
        DirectoryInfo[] subdir = dir.GetDirectories();
        if (subdir.Length > 0)
        {

            foreach (DirectoryInfo dr in subdir)
            {
                FileInfo[] files1 = dr.GetFiles();
                foreach (FileInfo file in files1)
                {
                    if(file.Name.EndsWith(".cs"))
                    CheckAndAdd((file.DirectoryName + "\\" + file.Name), FileList);
                }

            }
        }
    }

    private void AllFolderList(string FolderPath)
    {
        string CurFolderPatgh = FolderPath;
        Again:
        AddToArrayList(CurFolderPatgh);
        DirectoryInfo dir = new DirectoryInfo(CurFolderPatgh);
        DirectoryInfo[] subdir = dir.GetDirectories();

        if (subdir.Length > 0)
        {
            foreach (DirectoryInfo dr in subdir)
            {
                AddToArrayList(((System.IO.FileSystemInfo)(dir)).FullName + "\\" + dr.Name);
            }
        }
        if (FolderListSearch.Count > 0)
        {
            foreach (string dr in FolderListSearch)
            {
                CurFolderPatgh = dr;
                FolderListSearch.Remove(dr);
                goto Again;
            }
        }
    }

    private void AddToArrayList(string FolderPath)
    {
        if (!(FolderList.Contains(FolderPath)))
        {
            CheckAndAdd(FolderPath, FolderList);
            CheckAndAdd(FolderPath, FolderListSearch);
        }
    }

    private void CheckAndAdd(string FolderPath,ArrayList ar)
    {
        if (!(ar.Contains(FolderPath)))
        {
            ar.Add(FolderPath);
        }
    }

    public static void ReplaceInFile(
                      string filePath, string searchText, string replaceText)
    {

        var content = string.Empty;
        using (StreamReader reader = new StreamReader(filePath))
        {
            content = reader.ReadToEnd();
            reader.Close();
        }

        content = content.Replace(searchText, replaceText);

        using (StreamWriter writer = new StreamWriter(filePath))
        {
            writer.Write(content);
            writer.Close();
        }
    }
}

Answer 2

using System;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Linq;

namespace DevExpressFileEditing
{
    class Program
    {
        static List<FileInfo> _files;
        private static Dictionary<string, string> _replaceList;

        static void Main()
        {
            _files = new List<FileInfo>();
            _replaceList = new Dictionary<string, string>();

            Console.WriteLine("Dark directory searching");
            SearchFilesInDirectories(new DirectoryInfo(@"C:\Sourcebank\Dark"));

            Console.WriteLine("Light directory searching");
            SearchFilesInDirectories(new DirectoryInfo(@"C:\Sourcebank\Light"));

            Console.WriteLine("{0} files found", _files.Count.ToString(CultureInfo.InvariantCulture));

            Console.WriteLine("Replace dictinary creating");
            CreateReplaceList();
            Console.WriteLine("{0} item added", _replaceList.Count.ToString(CultureInfo.InvariantCulture));

            Console.Write("Replacement doing");
            for (int i = 0; i < _files.Count; i++)
            {
                var fileInfo = _files[i];
                Console.CursorLeft = 0;
                Console.Write("{0} of {1}", i.ToString(CultureInfo.InvariantCulture), _files.Count.ToString(CultureInfo.InvariantCulture));
                ReplaceInFile(fileInfo.FullName);
            }
            Console.CursorLeft = 0;
            Console.Write("Replacement done");
        }

        private static void SearchFilesInDirectories(DirectoryInfo dir)
        {
            if (!dir.Exists) return;

            foreach (DirectoryInfo subDirInfo in dir.GetDirectories())
                SearchFilesInDirectories(subDirInfo);

            foreach (var fileInfo in dir.GetFiles())
                _files.Add(fileInfo);
        }

        private static void CreateReplaceList()
        {
            _replaceList.Add("Color=\"#FFF78A09\"", "Color=\"{DynamicResource AccentColor}\"");
            _replaceList.Add("Color=\"{StaticResource ColorHot}\"", "Color=\"{DynamicResource AccentColor}\"");
            _replaceList.Add("Color=\"#FFCC0000\"", "Color=\"{DynamicResource AccentColor}\"");
            _replaceList.Add("To=\"#FFCC0000\"", "To=\"{DynamicResource AccentColor}\"");
            _replaceList.Add("To=\"#FFF78A09\"", "To=\"{DynamicResource AccentColor}\"");
            _replaceList.Add("Background=\"#FFF78A09\"", "Background=\"{DynamicResource Accent}\"");
            _replaceList.Add("Foreground=\"#FFF78A09\"", "Foreground=\"{DynamicResource Accent}\"");
            _replaceList.Add("BorderBrush=\"#FFF78A09\"", "BorderBrush=\"{DynamicResource Accent}\"");
            _replaceList.Add("Value=\"#FFF78A09\"", "Value=\"{DynamicResource Accent}\"");
            _replaceList.Add("Fill=\"#FFF78A09\"", "Fill=\"{DynamicResource Accent}\"");
        }

        public static void ReplaceInFile(string filePath)
        {
            string content;
            using (var reader = new StreamReader(filePath))
            {
                content = reader.ReadToEnd();
                reader.Close();
            }

            content = _replaceList.Aggregate(content, (current, item) => current.Replace(item.Key, item.Value));

            using (var writer = new StreamWriter(filePath))
            {
                writer.Write(content);
                writer.Close();
            }
        }
    }
}

Answer 3

Can be done in one line:

File.WriteAllText("Path", Regex.Replace(File.ReadAllText("Path"), "[Pattern]", "Replacement"));

Answer 4

Slight improvement on the accepted answer that doesn't require Regex, and which meets the requirements of the question:

File.WriteAllText("Path", File.ReadAllText("Path").Replace("SearchString", "Replacement"));

Answer 5

If you're reading large files in, and you string for replacement may not appear broken across multiple lines, I'd suggest something like the following...

private static void ReplaceTextInFile(string originalFile, string outputFile, string searchTerm, string replaceTerm)
{
    string tempLineValue;
    using (FileStream inputStream = File.OpenRead(originalFile) )
    {
        using (StreamReader inputReader = new StreamReader(inputStream))
        {
            using (StreamWriter outputWriter = File.AppendText(outputFile))
            {
                while(null != (tempLineValue = inputReader.ReadLine()))
                {
                    outputWriter.WriteLine(tempLineValue.Replace(searchTerm,replaceTerm));
                }
            }
        }
    }
}

Then you'd have to remove the original file, and rename the new one to the original name, but that's trivial - as is adding some basic error checking into the method.

Of course, if your replacement text could be across two or more lines, you'd have to do a little more work, but I'll leave that to you to figure out. :)

Answer 6

using System;
using System.IO;
using System.Text.RegularExpressions;

public static void ReplaceInFile(
                      string filePath, string searchText, string replaceText )
{

    var content = string.Empty;
    using (StreamReader reader = new StreamReader( filePath ))
    {
        content = reader.ReadToEnd();
        reader.Close();
    }

    content = Regex.Replace( content, searchText, replaceText );

    using (StreamWriter writer = new StreamWriter( filePath ))
    {
        writer.Write( content );
        writer.Close();
    }
}