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How to read a text file's data vertically or column wise

How can we read a text file column by column.
Check my new code: I can read the data row-wise using text.split (' ')
But how can be the file read as column wise? Lets assume that a file contains number of rows and columns but I was able to read the data/value horizontally. The code you see that below that's what I could execute!
SEE THE CODE BELOW:-
private void Form1_Load(object sender, EventArgs e)
{
}
private void textBox1_TextChanged(object sender, EventArgs e)
{
}
private void button1_Click(object sender, EventArgs e)
{
string text = "";
text = textBox1.Text;
string[] arr = text.Split(' ');
textBox2.Text = arr[5];
textBox3.Text = arr[8];
}
private void button3_Click(object sender, EventArgs e)
{
string file_name = "c:\\Excel\\count.txt";
string txtline = "";
System.IO.StreamReader objreader;
objreader = new System.IO.StreamReader(file_name);
do
{
txtline = txtline + objreader.ReadLine() + "\r\n";
txtline = txtline + objreader.ReadToEnd() + "";
this.textBox1.Text = "subzihut";
}
while (objreader.Peek() != -1);
textBox1.Text = txtline;
objreader.Close();
}
private void button2_Click(object sender, EventArgs e)
{
textBox4.Text = textBox2.Text + " " + textBox3.Text;
}
}
}

A textfile contains a sequence of characters, delimited by newline characters and probably other characters which are used as delimiters (usually a comma or a semiciolon).
When you read a file you simply read this stream of characters. There are helper functions which read such a file line-by-line (using the newline character as a delimiter).
In plain .Net there are no methods which read column-by-column.
So you should:
read the file line by line
split each line into fields/columns using string.Split() at the separator character(s)
access only the columns of interest

You can simply read the file line by line, splitt the lines and do whatever you want.
var lines = File.ReadLines(#"c:\yourfile.txt");
foreach(var line in lines)
{
var values = line.Split(' ');
}

public string getColumnString(int columnNumber){
string[] lines = System.IO.ReadAllLines(#"C:\inputfile.txt");
string stringTobeDisplayed = string.Empty;
foreach(string line in lines) {
if(columnNumber == -1){ //when column number is sent as -1 then read full line
stringTobeDisplayed += line +"\n"
}
else{ //else read only the column required
string [] words = line.Split();
stringTobeDisplayed += word[columnNumber] +"\n"
}
}
return stringTobeDisplayed;
}

Maybe this will help you:
public static void ReadFile(string path)
{
List<string> Col1 = new List<string>();
List<string> Col2 = new List<string>();
List<string> Col3 = new List<string>();
using (StreamReader sr = new StreamReader(path))
{
while (sr.EndOfStream)
{
string header = sr.ReadLine();
var values = header.Split(' ');
Col1.Add(values[0]);
Col2.Add(values[1]);
Col3.Add(values[2]);
}
}
}

It's true that sometimes you just don't know where to start. Here are some pointers.
You'll have to read the whole file in, probably using something like a StreamReader.
You can parse the first row into column names. Use StreamReader.ReadLine() to get the first line and then do some simple string parsing on it.
You'll want to create some kind of class/object to store and access your data.
Once you have column names, continue to parse the following lines into the proper arrays.
Some here's a rough idea
using(StreamReader sr = new StreamReadeR("C:\\my\\file\\location\\text.csv"))
{
string header = sr.ReadLine();
List<string> HeaderColumns = new List<string>(header.split(" ", StringSplitOptions.RemoveEmptyEntires));
myModelClass.Header = HeaderColumns;
etc...
You might also consider making some kind of dictionary to access columns by header name and index.

How to read textfile line by line into RichTextbox

I have a textfile which contains texts.Now as per my requirement i have to read this textfile line by line into the richtextbox.At present i am reading all lines of the text file at once into richtextbox.Here is my code ..
richTextBox1.Text = File.ReadAllText("E:\\vikas\\abc.txt");
But i want to display the texts of the textfile into richtextbox line by line.

Something like
List<string> lines = File.ReadLines ("E:\\vikas\\abc.txt").ToList();
foreach (string current in lines)
{
richTextBox1.Text += current;
}

not checked, but you just do something like this. you do not want to read it straight into a textbox, because that is slow!!!
using(StreamReader sr = new StreamReader(filename)
{
StringBuilder sb = new StringBuilder();
While(sr.Peek() >-1)
{
sb.Append( sr.ReadLine() );
}
The_Textbox.Text = sb.ToString();
}

Read last empty line of a text file

I have funny problem - I tried several scripts that will read text files, and that's ok.
Problem occur when text file have empty line at the end - that line is "ignored".
Code I use is "usual" code for file read, like next one:
string fullFileName;
fullFileName = "myFile.txt";
var lines = File.ReadAllLines(fullFileName);
string fileContent = null;
bool firstLine = true;
foreach (var line in lines) {
if (firstLine != true)
{
//textBox1.Text += System.Environment.NewLine;
fileContent += System.Environment.NewLine;
}
else
{
firstLine = false;
}
//textBox1.Text += line;
fileContent += line;
}
textBox1.Text = fileContent;
So, if last line of file myFile.txt is empty, it is not showed in a TextBox.
Can you help me where is a problem?

I think you could avoid the loop altogether and just do:
textBox1.Text = File.ReadAllText(fullFileName);
This will preserve all the newlines.

It is a problem with the file representation, not with ReadAllLines.
See this thread: http://www.pcreview.co.uk/forums/file-readalllines-doesnt-read-last-blank-line-weird-t3765200.html

Other solution:
using (FileStream fileStream = File.OpenRead("C:\myFile.txt"))
using (StreamReader streamReader = new StreamReader(fileStream))
{
string fileContent = streamReader.ReadToEnd();
textBox1.Text = fileContent;
}

File.ReadAllLines(fullFileName);
does not reads carriage return ('\r'). i think your last line contains only carriage return thats why its not being read. put space in last line to check.
http://msdn.microsoft.com/en-us/library/s2tte0y1.aspx

how to change a line in a txt-document with C#

I'm having a problem here. I have a .txt-file where one line contains "message", this is the line I wanna change. But I can't get this code to work, anyone that can help me?
I have this code here that is working for only replacing a string, but I don't know how to do it so it changes the whole line.
public void t()
{
string filename = #"F:\test\test.txt";
StringBuilder result = new StringBuilder();
if (System.IO.File.Exists(filename))
{
using (StreamReader streamReader = new StreamReader(filename))
{
String line;
while ((line = streamReader.ReadLine()) != null)
{
string newLine = String.Concat(line, Environment.NewLine);
newLine = newLine.Replace("message", "HEJHEJ ");
result.Append(newLine);
}
}
}
using (FileStream fileStream = new FileStream(filename, FileMode.Open, FileAccess.ReadWrite))
{
StreamWriter streamWriter = new StreamWriter(fileStream);
streamWriter.Write(result);
streamWriter.Close();
fileStream.Close();
}
}
This code is changeing "" to "HEJHEJ", but I want to whole line in the txt-document to change to "HEJHEJ", not just only the "message" part

How about changing this:
string newLine = String.Concat(line, Environment.NewLine);
newLine = newLine.Replace("message", "HEJHEJ ");
result.Append(newLine);
to this:
string newLine;
if (line.Contains("message")) {
newLine = String.Concat("HEJHEJ ", Environment.NewLine);
}
else {
newLine = String.Concat(line, Environment.NewLine);
}
result.Append(newLine);
There's a lot cleaner ways to do this, of course.

I have my txt-document with the line:
message helloworld
with your code this line changes into:
HEJHEJ
elloworld
//I would like it to be:
HEJHEJ
So in the end, i want it to change/replace to whole line of text that contains "message"

Parsing individual lines in a robots.txt file with C#

Working on an application to parse robots.txt. I wrote myself a method that pulled the the file from a webserver, and threw the ouput into a textbox. I would like the output to display a single line of text for every line thats in the file, just as it would appear if you were looking at the robots.txt normally, however the ouput in my textbox is all of the lines of text without carriage returns or line breaks. So I thought I'd be crafty, make a string[] for all the lines, make a foreach loop and all would be well. Alas that did not work, so then I thought I would try System.Enviornment.Newline, still not working. Here's the code as it sounds now....how can I change this so I get all the individual lines of robots.txt as opposed to a bunch of text cobbled together?
public void getRobots()
{
WebClient wClient = new WebClient();
string url = String.Format("http://{0}/robots.txt", urlBox.Text);
try
{
Stream data = wClient.OpenRead(url);
StreamReader read = new StreamReader(data);
string[] lines = new string[] { read.ReadToEnd() };
foreach (string line in lines)
{
textBox1.AppendText(line + System.Environment.NewLine);
}
}
catch (WebException ex)
{
MessageBox.Show(ex.Message, null, MessageBoxButtons.OK);
}
}

You are reading the entire file into the first element of the lines array:
string[] lines = new string[] {read.ReadToEnd()};
So all your loop is doing is adding the whole contents of the file into the TextBox, followed by a newline character. Replace that line with these:
string content = read.ReadToEnd();
string[] lines = content.Split(new string[] { "\r\n", "\n" }, StringSplitOptions.None);
And see if that works.
Edit: an alternative and perhaps more efficient way, as per Fish's comment below about reading line by line—replace the code within the try block with this:
Stream data = wClient.OpenRead(url);
StreamReader read = new StreamReader(data);
while (read.Peek() >= 0)
{
textBox1.AppendText(read.ReadLine() + System.Environment.NewLine);
}

You need to make the textBox1 multiline. Then I think you can simply go
textBox1.Lines = lines;
but let me check that

Try
public void getRobots()
{
WebClient wClient = new WebClient();
string robotText;
string[] robotLines;
System.Text.StringBuilder robotStringBuilder;
robotText = wClient.DownloadString(String.Format("http://{0}/robots.txt", urlBox.Text));
robotLines = robotText.Split(Environment.NewLine);
robotStringBuilder = New StringBuilder();
foreach (string line in robotLines)
{
robotStringBuilder.Append(line);
robotStringBuilder.Append(Environment.NewLine);
}
textbox1.Text = robotStringBuilder.ToString();
}

Try using .Read() in a while loop instead of .ReadToEnd() - I think you're just getting the entire file as one line in your lines array. Debug and check the count of lines[] to verify this.
Edit: Here's a bit of sample code. Haven't tested it, but I think it should work OK;
Stream data = wClient.OpenRead(url);
StreamReader read = new StreamReader(data);
List<string> lines = new List<string>();
string nextLine = read.ReadLine();
while (nextLine != null)
{
lines.Add(nextLine);
nextLine = read.ReadLine();
}
textBox1.Lines = lines.ToArray();