Outputting the content of an array to a text file in C# - c#

I need your help.
I want to make a program where I give a number and it increments it as many times as I said and write output into a .txt file. I have an issue with writing it because it only writes one output. I know basics but I have never worked with more complicated coding, only a few games, and simple apps.
int baseNumber = int.Parse(tbBase.Text);
int codeNumber = int.Parse(tbCodeNumber.Text);
int[] codes = new int[codeNumber];
int count = 0;
string link = "https://www.roblox.com/groups/";
for (int i =0; i < codes.Length; i++)
{
codes[i] = baseNumber++;
}
foreach (int element in codes)
{
string text= $"{link}{Convert.ToString(codes[count])}";
System.IO.File.WriteAllText(#"D:\TextFiles\WriteText.txt", text);
count++;
}

you can use this code . You wrote the number of for loops in the file, which is wrong. Put the text in a string and put it in the file
int baseNumber = int.Parse(tbBase.Text);
int codeNumber = int.Parse(tbCodeNumber.Text);
int[] codes = new int[codeNumber];
for (int i = 0; i < codes.Length; i++)
{
codes[i] = baseNumber++;
}
int count = 0;
string text = "";
string link = "https://www.roblox.com/groups/";
foreach (int element in codes)
{
text += $"{link}{Convert.ToString(codes[count])}";
count++;
}
string fileName = #"D:\WriteText.txt";
if (File.Exists(fileName))
System.IO.File.AppendAllText(fileName, text);
else
System.IO.File.WriteAllText(fileName, text);
Read text file for editing
public void ReadFile(string fileName)
{
string[] lines = System.IO.File.ReadAllLines(fileName);
// Display the file contents by using a foreach loop.
string text = "";
foreach (string line in lines)
{
// Use a tab to indent each line of the file.
text += line + Environment.NewLine;
Console.WriteLine("\t" + line);
}
}

Related

Parsing a huge text file(around 2GB) with custom delimiters

I have a huge text file around 2GB which I am trying to parse in C#.
The file has custom delimiters for rows and columns. I want to parse the file and extract the data and write to another file by inserting column header and replacing RowDelimiter by newline and ColumnDelimiter by tab so that I can get the data in tabular format.
sample data:
1'~'2'~'3#####11'~'12'~'13
RowDelimiter: #####
ColumnDelimiter: '~'
I keep on getting System.OutOfMemoryException on the following line
while ((line = rdr.ReadLine()) != null)
public void ParseFile(string inputfile,string outputfile,string header)
{
using (StreamReader rdr = new StreamReader(inputfile))
{
string line;
while ((line = rdr.ReadLine()) != null)
{
using (StreamWriter sw = new StreamWriter(outputfile))
{
//Write the Header row
sw.Write(header);
//parse the file
string[] rows = line.Split(new string[] { ParserConstants.RowSeparator },
StringSplitOptions.None);
foreach (string row in rows)
{
string[] columns = row.Split(new string[] {ParserConstants.ColumnSeparator},
StringSplitOptions.None);
foreach (string column in columns)
{
sw.Write(column + "\\t");
}
sw.Write(ParserConstants.NewlineCharacter);
Console.WriteLine();
}
}
Console.WriteLine("File Parsing completed");
}
}
}
As mentioned already in the comments you won't be able to use ReadLine to handle this, you'll have to essentially process the data one byte - or character - at a time. The good news is that this is basically how ReadLine works anyway, so we're not losing a lot in this case.
Using a StreamReader we can read a series of characters from the source stream (in whatever encoding you need) into an array. Using that and a StringBuilder we can process the stream in chunks and check for separator sequences on the way.
Here's a method that will handle an arbitrary delimiter:
public static IEnumerable<string> ReadDelimitedRows(StreamReader reader, string delimiter)
{
char[] delimChars = delimiter.ToArray();
int matchCount = 0;
char[] buffer = new char[512];
int rc = 0;
StringBuilder sb = new StringBuilder();
while ((rc = reader.Read(buffer, 0, buffer.Length)) > 0)
{
for (int i = 0; i < rc; i++)
{
char c = buffer[i];
if (c == delimChars[matchCount])
{
if (++matchCount >= delimChars.Length)
{
// found full row delimiter
yield return sb.ToString();
sb.Clear();
matchCount = 0;
}
}
else
{
if (matchCount > 0)
{
// append previously matched portion of the delimiter
sb.Append(delimChars.Take(matchCount));
matchCount = 0;
}
sb.Append(c);
}
}
}
// return the last row if found
if (sb.Length > 0)
yield return sb.ToString();
}
This should handle any cases where part of your block delimiter can appear in the actual data.
In order to translate your file from the input format you describe to a simple tab-delimited format you could do something along these lines:
const string RowDelimiter = "#####";
const string ColumnDelimiter = "'~'";
using (var reader = new StreamReader(inputFilename))
using (var writer = new StreamWriter(File.Create(ouputFilename)))
{
foreach (var row in ReadDelimitedRows(reader, RowDelimiter))
{
writer.Write(row.Replace(ColumnDelimiter, "\t"));
}
}
That should process fairly quickly without eating up too much memory. Some adjustments might be required for non-ASCII output.
Read the data into a buffer and then do your parsing.
using (StreamReader rdr = new StreamReader(inputfile))
using (StreamWriter sw = new StreamWriter(outputfile))
{
char[] buffer = new char[256];
int read;
//Write the Header row
sw.Write(header);
string remainder = string.Empty;
while ((read = rdr.Read(buffer, 0, 256)) > 0)
{
string bufferData = new string(buffer, 0, read);
//parse the file
string[] rows = bufferData.Split(
new string[] { ParserConstants.RowSeparator },
StringSplitOptions.None);
rows[0] = remainder + rows[0];
int completeRows = rows.Length - 1;
remainder = rows.Last();
foreach (string row in rows.Take(completeRows))
{
string[] columns = row.Split(
new string[] {ParserConstants.ColumnSeparator},
StringSplitOptions.None);
foreach (string column in columns)
{
sw.Write(column + "\\t");
}
sw.Write(ParserConstants.NewlineCharacter);
Console.WriteLine();
}
}
if(reamainder.Length > 0)
{
string[] columns = remainder.Split(
new string[] {ParserConstants.ColumnSeparator},
StringSplitOptions.None);
foreach (string column in columns)
{
sw.Write(column + "\\t");
}
sw.Write(ParserConstants.NewlineCharacter);
Console.WriteLine();
}
Console.WriteLine("File Parsing completed");
}
The problem you have is that you are eagerly consuming the whole file and placing it in memory. Attempting to split a 2GB file in memory is going to be problematic, as you now know.
Solution? Consume one lime a time. Because your file doesn't have a standard line separator you'll have to implement a custom parser that does this for you. The following code does just that (or I think it does, I haven't tested it). Its probably very improvable from a performance perspective but it should at least get you started in the right direction (c#7 syntax):
public static IEnumerable<string> GetRows(string path, string rowSeparator)
{
bool tryParseSeparator(StreamReader reader, char[] buffer)
{
var count = reader.Read(buffer, 0, buffer.Length);
if (count != buffer.Length)
return false;
return Enumerable.SequenceEqual(buffer, rowSeparator);
}
using (var reader = new StreamReader(path))
{
int peeked;
var rowBuffer = new StringBuilder();
var separatorBuffer = new char[rowSeparator.Length];
while ((peeked = reader.Peek()) > -1)
{
if ((char)peeked == rowSeparator[0])
{
if (tryParseSeparator(reader, separatorBuffer))
{
yield return rowBuffer.ToString();
rowBuffer.Clear();
}
else
{
rowBuffer.Append(separatorBuffer);
}
}
else
{
rowBuffer.Append((char)reader.Read());
}
}
if (rowBuffer.Length > 0)
yield return rowBuffer.ToString();
}
}
Now you have a lazy enumeration of rows from your file, and you can process it as you intended to:
foreach (var row in GetRows(inputFile, ParserConstants.RowSeparator))
{
var columns = line.Split(new string[] {ParserConstants.ColumnSeparator},
StringSplitOptions.None);
//etc.
}
I think this should do the trick...
public void ParseFile(string inputfile, string outputfile, string header)
{
int blockSize = 1024;
using (var file = File.OpenRead(inputfile))
{
using (StreamWriter sw = new StreamWriter(outputfile))
{
int bytes = 0;
int parsedBytes = 0;
var buffer = new byte[blockSize];
string lastRow = string.Empty;
while ((bytes = file.Read(buffer, 0, buffer.Length)) > 0)
{
// Because the buffer edge could split a RowDelimiter, we need to keep the
// last row from the prior split operation. Append the new buffer to the
// last row from the prior loop iteration.
lastRow += Encoding.Default.GetString(buffer,0, bytes);
//parse the file
string[] rows = lastRow.Split(new string[] { ParserConstants.RowSeparator }, StringSplitOptions.None);
// We cannot process the last row in this set because it may not be a complete
// row, and tokens could be clipped.
if (rows.Count() > 1)
{
for (int i = 0; i < rows.Count() - 1; i++)
{
sw.Write(new Regex(ParserConstants.ColumnSeparator).Replace(rows[i], "\t") + ParserConstants.NewlineCharacter);
}
}
lastRow = rows[rows.Count() - 1];
parsedBytes += bytes;
// The following statement is not quite true because we haven't parsed the lastRow.
Console.WriteLine($"Parsed {parsedBytes.ToString():N0} bytes");
}
// Now that there are no more bytes to read, we know that the lastrow is complete.
sw.Write(new Regex(ParserConstants.ColumnSeparator).Replace(lastRow, "\t"));
}
}
Console.WriteLine("File Parsing completed.");
}
Late to the party here, but in case anyone else want to know easy way to load such large CSV file with custom delimiters, Cinchoo ETL does the job for you.
using (var parser = new ChoCSVReader("CustomNewLine.csv")
.WithDelimiter("~")
.WithEOLDelimiter("#####")
)
{
foreach (dynamic x in parser)
Console.WriteLine(x.DumpAsJson());
}
Disclaimer: I'm the author of this library.

How to delete a specific record (fixed length) includes data from a .txt file?

I am new in C# and I am making project but I can't make this delete part ..
If I save my data in .txt file in one line, but contain many fixed length record with no delimiter, if each record has fixed length and each field has fixed length and saved in file like this
1ahly2zamalek
how do I delete, for example the record 2zamalek from line with entering to the program id=2?
public team()
{
Team_ID_Len = 5;
Team_Name_Len = 10;
Team_Rec_Len = 15; ;
Team_ID = new char[Team_ID_Len];
Team_Name = new char[Team_Name_Len];
}
Sounds like you're looking for Substring. Give it a start (length of record * how many), and the length (length of record).
Actually, you might want to create the string as string s = part1+part2 where part1 is the substring from 0 till the start of the record, and part2 is the start of the NEXT record, until the end.
Then just save it.
Your number is your delimiter, split with a char array
using System;
using System;
public static class Program
{
public static void Main()
{
string words = "1sdklfjlsdf2lksjdf3sfd4sfd5fsd6fsd7fsd8fsd9sfd10aslkdfj11jklh12hjk";
int deleteRecordId = 11;
string [] split = words.Split(new Char [] {'1', '2','3','4','5','6','7','8','9','0'});
string newString = "";
int j = 0;
for( int i = 0; i < split.Length; i++)
{
if ( j == deleteRecordId)
{
//ignore this record
Console.WriteLine("ignore i = " + i);
j++;
}
else
{
Console.WriteLine("i = " + i);
if(!( split[i] == ""))
{
newString += j + split[i];
j++;
}
}
}
Console.WriteLine(newString);
}
}
then WriteAll to the file

C# Split not working

I'm trying to read data from a file, split the data and save to array. The code works fine except for the split. It is returning a NullException.
Any help would be greatly appreciated.
public static void LoadHandData(CurrentHand[] handData, string fileName)
{
string input = ""; //temporary variable to hold one line of data
string[] cardData; //temporary array to hold data split from input
StreamReader readHand = new StreamReader(fileName);
for (int counter = 0; counter < handData.Length; counter++)
{
input = readHand.ReadLine(); //one record
cardData = input.Split(' '); //split record into fields
int index = 0;
handData[counter].cardSuit = Convert.ToChar(cardData[index++]);
handData[counter].cardValue = Convert.ToInt16(cardData[index++]);
}
readHand.Close();
}
As per the comments, you've only got one line of data. But look at your loop:
for (int counter = 0; counter < handData.Length; counter++)
{
input = readHand.ReadLine(); //one record
cardData = input.Split(' '); //split record into fields
int index = 0;
handData[counter].cardSuit = Convert.ToChar(cardData[index++]);
handData[counter].cardValue = Convert.ToInt16(cardData[index++]);
}
That's trying to read one line per hand. On the second iteration, ReadLine will return null, so when you call input.Split() you'll end up with the NullReferenceException you're seeing.
You need to read the line once and split it. Given that you've only got one line of text, you can just use File.ReadAllText to simplify things:
string input = File.ReadAllText(fileName);
string[] cardData = input.Split(' ');
for (int counter = 0; counter < handData.Length; counter++)
{
handData[counter].cardSuit = Convert.ToChar(cardData[counter * 2]);
handData[counter].cardValue = Convert.ToInt16(cardData[counter * 2 + 1]);
}

Auto Incrementing file names?

I have a list of files like so
abc.txt
pas.txt
tempr.txt
What I would like to do is to append english alphabets to theese file names ..
the result should look like this
abc_a.txt
pas_b.txt
tempr_c.txt
This process should continue till the last character (i.e 'z'). if there are more files then the file names would become
abc_a.txt
pas_b.txt
tempr_c.txt
.................
filename_z.txt
anotherfilename_a001.txt
Notice that the counter was again reset to the first character except an integer was attached to it.
This is the code that i have right now. Please note that it is NOT working ..
string alphabets= "abcdefghijklmnopqrstuvwxyz";
List<string> filenames = new List<string>();
filenames.Add("test1.txt");
filenames.Add("newfile.cs");
filenames.Add("test2.txt");
filenames.Add("newfile2.cs");
string currentFileNmae = string.Empty;
foreach(string s in filenames) {
char usedAlphabet = new char();
for(int i = 0;i<=alphabets.Length-1;i+=11) {
usedAlphabet.Dump();
alphabets[i].Dump();
if(usedAlphabet != alphabets[i] )
{
if(currentFileNmae!= s)
{
string.Format("{0}--{1}",s,alphabets[i]).Dump();
usedAlphabet = alphabets[i];
currentFileNmae = s;
}
}
break;
}
}
I am part of a team that's building a file renamer tool for our internal purposes and hence i need this code. This is part of the our enumertation functionality that we have planned.
Please suggest.
thanks
Try starting here:
using System.Diagnostics;
using System.IO;
string filename = #"C:\Foo\Bar.txt";
for (int count = 0; count < 100; count++)
{
char letter = (char)((int)'a' + count % 26);
string numeric = (count / 26) == 0 ? "" : (count / 26).ToString("000");
Debug.Print(Path.GetFileNameWithoutExtension(filename) + "_" + letter + numeric + Path.GetExtension(filename));
}
Substitute your own loop to go through the filenames and use Path to manipulate the pieces/parts of the names.
The renaming, IIRC, can be handled by File.Move. Surround it with a try/catch to implement the name collision logic.
Had no coffee yet, but this should do.
List<string> files = new List<string>();
int charIndex = 0;
int numericIndex = -1;
foreach (var file in files.Select(path => new FileInfo(path)))
{
// Create new Filename - This may needs some tuning
// to really remove only the extension ad the end
// It doesnt take care of things like
// file.bmp.bmp.bmp ...
string newFileName = String.Format("{0}_{1}{2}.{3}",
file.FullName.Replace(file.Extension,String.Empty),
(char)(charIndex++ + 97),
(numericIndex > -1 ? String.Format("{0:D4}", numericIndex) : String.Empty),
file.Extension);
// Rename the File
file.MoveTo(newFileName);
// Increment Counters.
if (charIndex > 25)
{
charIndex = 0;
numericIndex++;
}
}
You can try something like this
const string directory = #"C:\\wherever";
string[] fiNames = new string[]{ "abc", "pas", "etc",};
char[] alphabet = "abcdefghijklmnopqrstuvwxyz".ToCharArray();
int x = 0;
string ending = "";
for(int i = fiNames.Count()-1; i>=0; i--)
{
if(x%26==0)
{
x=0
if( ending=="")
ending="1";
else
ending=(System.Convert.ToInt32(ending)+1).ToString();
}
System.IO.File.Move(directory+fiNames[i], fiNames[i]+alphabet[x].ToString()+ending);
x++;
}

load .txt file into gridview c#

So im nearly there, just need to load the information from my text file in notepad which is saved like so:
item1
item2
item3
item4
My first attempt was this:
gridProfiles.Columns.Add("App Name", "Active");
int i = 0;
foreach(char snif in "D:\\ProfileAppName.txt")
{
gridProfiles.Rows.Add();
gridProfiles.Rows[i].Cells[0].Value = snif;
i++;
}
But this just loaded the file name into the text file
My next attempt was:
gridProfiles.Columns.Add("App Name", "Active");
int i = 0;
foreach (string snif in "D:\\ProfileAppName.txt")
{
string[] values = snif.Split(' ');
int j = 0;
foreach (string value in values)
{
gridProfiles.Rows.Add();
gridProfiles.Rows[i].Cells[0].Value = snif;
j++;
}
}
i++;
But i get the error "cannot convert type 'char' into 'string'
Can anyone help me? im nearly there but cant get my finger on it
You are looping all chars in this string: "D:\\ProfileAppName.txt". I assume you want to loop all lines in the file. Then you can use File.ReadLines:
foreach(string line in File.ReadLines("D:\\ProfileAppName.txt"))
{
gridProfiles.Rows.Add();
gridProfiles.Rows[i].Cells[0].Value = line;
i++;
}
The read the content of the file you could do this:
int i = 0;
foreach(string row in File.ReadAllLines("D:\\ProfileAppName.txt"))
{
if (i % 2 == 0)
gridProfiles.Rows.Add();
gridProfiles.Rows[i / 2].Cells[i % 2].Value = line;
i++;
}

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