Unable to replace string from text file

Question

The code I'm trying to write is to replace a string of words within a text file. Though I'm able to read the file's content to console, I'm unable to replace the string of words and write a new string to the file.

Here's my code:

private static void filesys_created (object sender, FileSystemEventArgs e)
{
    using (StreamReader sr = new StreamReader(e.FullPath))
    {
        Console.WriteLine(sr.ReadToEnd());
        File.ReadAllText(e.FullPath);
        sr.Close();
    }

    using (StreamWriter sw = new StreamWriter(e.FullPath))
    {
        string text = e.FullPath.Replace("The words I want to replace");
        string newtext = "text I want it to be replaced with";

        sw.Write(e.FullPath, text);
        sw.Write(newtext);
        sw.Close();
    }
}

The problem is that the .Replace is deleting everything in the text file and only inserting the path of the directory.

stuartd · Accepted Answer · 2018-10-30T11:19:33.557

6

Well, the problems as I see it are a) you're reading the file but not assigning the text to a variable b) you're not actually doing a replace and c) you are indeed writing the file name to the output.

You don't need to use streams so your code can be simplified to this:

var contents = File.ReadAllText(e.FullPath);
contents = contents.Replace(text, newText);
File.WriteAllText(e.FullPath, contents);

It looks like you're using a FileSystemWatcher to pick up the file, so just noting that this will fire (at least) a Changed event.

edited Oct 30 '18 at 11:19

answered Oct 30 '18 at 11:05

stuartd

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2

Thank you Stuart! This resolved the problem:) – s4mdev Oct 30 '18 at 11:13

score 0 · Answer 2 · answered Oct 30 '18 at 11:08

You are writing the FullPath into the file, try this:

var text = null;
using (StreamReader sr = new StreamReader(e.FullPath))
{
    text = sr.ReadToEnd();
    Console.WriteLine(text);
}

using (StreamWriter sw = new StreamWriter(e.FullPath))
{
    var replaced = text.Replace("The words I want to replace", "text I want it to be replaced with");
    sw.Write(replaced);
}

Unable to replace string from text file

2 Answers2