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Replacing a certain word in a text file

I know this has been asked a few times, but I have seen a lot of regex etc., and I'm sure there is another way to do this with just a stream reader/writer. Below is my code. I'm trying to replace "tea" with the word "cabbage". Can somebody help? I believe I have the wrong syntax.
namespace Week_9_Exer_4
{
class TextImportEdit
{
public void EditorialControl()
{
string fileName;
string lineReadFromFile;
Console.WriteLine("");
// Ask for the name of the file to be read
Console.Write("Which file do you wish to read? ");
fileName = Console.ReadLine();
Console.WriteLine("");
// Open the file for reading
StreamReader fileReader = new StreamReader("C:\\Users\\Greg\\Desktop\\Programming Files\\story.txt");
// Read the lines from the file and display them
// until a null is returned (indicating end of file)
lineReadFromFile = fileReader.ReadLine();
Console.WriteLine("Please enter the word you wish to edit out: ");
string editWord = Console.ReadLine();
while (lineReadFromFile != null)
{
Console.WriteLine(lineReadFromFile);
lineReadFromFile = fileReader.ReadLine();
}
String text = File.ReadAllText("C:\\Users\\Greg\\Desktop\\Programming Files\\story.txt");
fileReader.Close();
StreamWriter fileWriter = new StreamWriter("C:\\Users\\Greg\\Desktop\\Programming Files\\story.txt", false);
string newText = text.Replace("tea", "cabbage");
fileWriter.WriteLine(newText);
fileWriter.Close();
}
}
}

If you don't care about memory usage:
string fileName = #"C:\Users\Greg\Desktop\Programming Files\story.txt";
File.WriteAllText(fileName, File.ReadAllText(fileName).Replace("tea", "cabbage"));
If you have a multi-line file that doesn't randomly split words at the end of the line, you could modify one line at a time in a more memory-friendly way:
// Open a stream for the source file
using (var sourceFile = File.OpenText(fileName))
{
// Create a temporary file path where we can write modify lines
string tempFile = Path.Combine(Path.GetDirectoryName(fileName), "story-temp.txt");
// Open a stream for the temporary file
using (var tempFileStream = new StreamWriter(tempFile))
{
string line;
// read lines while the file has them
while ((line = sourceFile.ReadLine()) != null)
{
// Do the word replacement
line = line.Replace("tea", "cabbage");
// Write the modified line to the new file
tempFileStream.WriteLine(line);
}
}
}
// Replace the original file with the temporary one
File.Replace("story-temp.txt", "story.txt", null);

In the end i used this : Hope it can help out others
public List<string> EditorialResponse(string fileName, string searchString, string replacementString)
{
List<string> list = new List<string>();
using (StreamReader reader = new StreamReader(fileName))
{
string line;
while ((line = reader.ReadLine()) != null)
{
line = line.Replace(searchString, replacementString);
list.Add(line);
Console.WriteLine(line);
}
reader.Close();
}
return list;
}
}
class Program
{
static void Main(string[] args)
{
TextImportEdit tie = new TextImportEdit();
List<string> ls = tie.EditorialResponse(#"C:\Users\Tom\Documents\Visual Studio 2013\story.txt", "tea", "cockrel");
StreamWriter writer = new StreamWriter(#"C:\Users\Tom\Documents\Visual Studio 2013\story12.txt");
foreach (string line in ls)
{
writer.WriteLine(line);
}
writer.Close();
}
}
}

c# read/store data in a file?

What I want to do is actually have my program open up and set a string array so that i can use it for if commands (its used to block people) and I want to store another string in there so that it can be saved and still be used if the program restart. Can someone show me how to do this? Please and thank you :]

You could use the following:
string[] lines = File.ReadAllLines(#"Path here").ToArray();
This splits each line up into the array.
As for saving to file, google "saving to file in c#", you will get plenty of results and tutorials.

This is definitely better then the solution I posted first:
File.WriteAllLines(fileName, yourStringArray);
yourStringArray = File.ReadAllLines(fileName);
File.WriteAllLines
File.ReadAllLines
Below my first answer. Correct, but crap!
Something like this should work for you. Don't blame me for inaccuracy, I am not wide awake yet! ;)
{
string fileName = #"d:\temp\blacklist.txt";
char seperator = ';';
public Form1()
{
InitializeComponent();
string[] users = { "Dave", "John", "Shawn" };
//Save(users);
users = Load();
}
public string[] Load()
{
string line;
using (StreamReader sr = new StreamReader(this.fileName))
{
line = sr.ReadToEnd();
}
return line.Split(seperator);
}
public void Save(string[] users)
{
using (StreamWriter sw = new StreamWriter(this.fileName))
{
string line = string.Empty;
foreach (string user in users)
{
line += string.Format("{0}{1}", user, seperator);
}
sw.WriteLine(line);
sw.Flush();
}
}
}

Rewriting a text file after reading it

i got a file that is store in my appliction directory, and he got some site list.
i dont have any problem reading it, but when i want to write to it, i get
System.ArgumentException: Stream is not writeable
this is how i accsess the file:
FileStream theTextFileStream = new FileStream(Environment.CurrentDirectory + "/fourmlinks.txt",FileMode.OpenOrCreate);
and this is the function that throw me the expection:
public static void WriteNewTextToFile(string text, FileStream theFile)
{
string fileText = GetAllTextFromFile(theFile);
ArrayList fileLIst = populateListFromText(fileText);
using (StreamWriter fileWriter = new StreamWriter(theFile))
{
fileWriter.Write(String.Empty);
for (int i = 0; i < fileLIst.Count; i++)
{
fileWriter.WriteLine(fileLIst[i].ToString());
}
}
}
the function read the old and new text and add it to an arry. then i clean the file from every thing, and rewriting it with the old and new data from the arry i made.
i dont know if that will help but here is the file proprites:
Build Action: None
Copy To Out Put Directory: Copy always
why i cant rewrite the file?
this is the function i use to read the file content:
public static string GetAllTextFromFile(FileStream theFile)
{
string fileText = "";
using (theFile)
{
using (StreamReader stream = new StreamReader(theFile))
{
string currentLine = "";
while ((currentLine = stream.ReadLine()) != null)
{
fileText += currentLine + "\n";
}
}
}
return fileText;
}

You have to use Read/Write file access as third parameter -
FileStream theTextFileStream = new FileStream(Environment.CurrentDirectory + "/fourmlinks.txt",FileMode.OpenOrCreate, FileAccess.ReadWrite
);
Important - Remove using(theFile) statement:
public static string GetAllTextFromFile(FileStream theFile)
{
string fileText = "";
using (StreamReader stream = new StreamReader(theFile))
{
string currentLine = "";
while ((currentLine = stream.ReadLine()) != null)
{
fileText += currentLine + "\n";
}
}
return fileText;
}
Do not use using construct in your case as it will close the underlying stream as in your case you have to manually open and close stream objects.
This will allow you to write in the file as well.
For more information refer following links -
FileStream Constructor
FileAccess Enumeration

Delete Lines in a textfile

Hi I have a text file with table schema and data when user checks not schema required then i need to delete schema and leave the data . I am using StreamReader to read the file and checking one condition and it should delete all the lines in the file till it satisfies my condition .
Let say if i am checking
using (StreamReader tsr = new StreamReader(targetFilePath))
{
do
{
string textLine = tsr.ReadLine() + "\r\n";
{
if (textLine.StartsWith("INSERT INTO"))
{
// It should leave these lines
// and no need to delete lines
}
else
{
// it should delete the lines
}
}
}
while (tsr.Peek() != -1);
tsr.Close();
Please suggest me how to delete lines and note if textline finds "InsertInto" it should not delete any content from there .

Use a second file where to put only required lines, and, at the end of the process, remove original file and rename new one to target file.
using (StreamReader tsr = new StreamReader(targetFilePath))
{
using (StreamWriter tsw = File.CreateText(targetFilePath+"_temp"))
{
string currentLine;
while((currentLine = tsr.ReadLine()) != null)
{
if(currentLine.StartsWith("A long time ago, in a far far away galaxy ..."))
{
tsw.WriteLine(currentLine);
}
}
}
}
File.Delete(targetFilePath);
File.Move(targetFilePath+"_temp",targetFilePath);

You could use Linq:
File.WriteAllLines(targetFilePath, File.ReadAllLines(targetFilePath).Where(x => x.StartsWith("INSERT INTO")));

You read in the file just the same way you were doing. However, if the line doesn't contain what you are looking for, you simply skip it. In the end, whatever data you are left over with you then write to a new text file.
private void button1_Click(object sender, EventArgs e)
{
StringBuilder newText = new StringBuilder();
using (StreamReader tsr = new StreamReader(targetFilePath))
{
do
{
string textLine = tsr.ReadLine() + "\r\n";
{
if (textLine.StartsWith("INSERT INTO"))
{
newText.Append(textLine + Environment.NewLine);
}
}
}
while (tsr.Peek() != -1);
tsr.Close();
}
System.IO.TextWriter w = new System.IO.StreamWriter(#"C:\newFile.txt");
w.Write(newText.ToString());
w.Flush();
w.Close();
}

Delete specific line from a text file?

I need to delete an exact line from a text file but I cannot for the life of me workout how to go about doing this.
Any suggestions or examples would be greatly appreciated?
Related Questions
Efficient way to delete a line from a text file (C#)

If the line you want to delete is based on the content of the line:
string line = null;
string line_to_delete = "the line i want to delete";
using (StreamReader reader = new StreamReader("C:\\input")) {
using (StreamWriter writer = new StreamWriter("C:\\output")) {
while ((line = reader.ReadLine()) != null) {
if (String.Compare(line, line_to_delete) == 0)
continue;
writer.WriteLine(line);
}
}
}
Or if it is based on line number:
string line = null;
int line_number = 0;
int line_to_delete = 12;
using (StreamReader reader = new StreamReader("C:\\input")) {
using (StreamWriter writer = new StreamWriter("C:\\output")) {
while ((line = reader.ReadLine()) != null) {
line_number++;
if (line_number == line_to_delete)
continue;
writer.WriteLine(line);
}
}
}

The best way to do this is to open the file in text mode, read each line with ReadLine(), and then write it to a new file with WriteLine(), skipping the one line you want to delete.
There is no generic delete-a-line-from-file function, as far as I know.

One way to do it if the file is not very big is to load all the lines into an array:
string[] lines = File.ReadAllLines("filename.txt");
string[] newLines = RemoveUnnecessaryLine(lines);
File.WriteAllLines("filename.txt", newLines);

Hope this simple and short code will help.
List linesList = File.ReadAllLines("myFile.txt").ToList();
linesList.RemoveAt(0);
File.WriteAllLines("myFile.txt"), linesList.ToArray());
OR use this
public void DeleteLinesFromFile(string strLineToDelete)
{
string strFilePath = "Provide the path of the text file";
string strSearchText = strLineToDelete;
string strOldText;
string n = "";
StreamReader sr = File.OpenText(strFilePath);
while ((strOldText = sr.ReadLine()) != null)
{
if (!strOldText.Contains(strSearchText))
{
n += strOldText + Environment.NewLine;
}
}
sr.Close();
File.WriteAllText(strFilePath, n);
}

You can actually use C# generics for this to make it real easy:
var file = new List<string>(System.IO.File.ReadAllLines("C:\\path"));
file.RemoveAt(12);
File.WriteAllLines("C:\\path", file.ToArray());

This can be done in three steps:
// 1. Read the content of the file
string[] readText = File.ReadAllLines(path);
// 2. Empty the file
File.WriteAllText(path, String.Empty);
// 3. Fill up again, but without the deleted line
using (StreamWriter writer = new StreamWriter(path))
{
foreach (string s in readText)
{
if (!s.Equals(lineToBeRemoved))
{
writer.WriteLine(s);
}
}
}

Read and remember each line
Identify the one you want to get rid
of
Forget that one
Write the rest back over the top of
the file

I cared about the file's original end line characters ("\n" or "\r\n") and wanted to maintain them in the output file (not overwrite them with what ever the current environment's char(s) are like the other answers appear to do). So I wrote my own method to read a line without removing the end line chars then used it in my DeleteLines method (I wanted the option to delete multiple lines, hence the use of a collection of line numbers to delete).
DeleteLines was implemented as a FileInfo extension and ReadLineKeepNewLineChars a StreamReader extension (but obviously you don't have to keep it that way).
public static class FileInfoExtensions
{
public static FileInfo DeleteLines(this FileInfo source, ICollection<int> lineNumbers, string targetFilePath)
{
var lineCount = 1;
using (var streamReader = new StreamReader(source.FullName))
{
using (var streamWriter = new StreamWriter(targetFilePath))
{
string line;
while ((line = streamReader.ReadLineKeepNewLineChars()) != null)
{
if (!lineNumbers.Contains(lineCount))
{
streamWriter.Write(line);
}
lineCount++;
}
}
}
return new FileInfo(targetFilePath);
}
}
public static class StreamReaderExtensions
{
private const char EndOfFile = '\uffff';
/// <summary>
/// Reads a line, similar to ReadLine method, but keeps any
/// new line characters (e.g. "\r\n" or "\n").
/// </summary>
public static string ReadLineKeepNewLineChars(this StreamReader source)
{
if (source == null)
throw new ArgumentNullException(nameof(source));
char ch = (char)source.Read();
if (ch == EndOfFile)
return null;
var sb = new StringBuilder();
while (ch != EndOfFile)
{
sb.Append(ch);
if (ch == '\n')
break;
ch = (char)source.Read();
}
return sb.ToString();
}
}

Are you on a Unix operating system?
You can do this with the "sed" stream editor. Read the man page for "sed"

What?
Use file open, seek position then stream erase line using null.
Gotch it? Simple,stream,no array that eat memory,fast.
This work on vb.. Example search line culture=id where culture are namevalue and id are value and we want to change it to culture=en
Fileopen(1, "text.ini")
dim line as string
dim currentpos as long
while true
line = lineinput(1)
dim namevalue() as string = split(line, "=")
if namevalue(0) = "line name value that i want to edit" then
currentpos = seek(1)
fileclose()
dim fs as filestream("test.ini", filemode.open)
dim sw as streamwriter(fs)
fs.seek(currentpos, seekorigin.begin)
sw.write(null)
sw.write(namevalue + "=" + newvalue)
sw.close()
fs.close()
exit while
end if
msgbox("org ternate jua bisa, no line found")
end while
that's all..use #d