I want to merge 2 .txt files into one text file. Let's say I have 2 text files. First one contains 100 rows only "Try Again". Like this one in the picture:
And the second text file contains bunch of random codes:
I want to merge these 2 text files, like this one in the picture below:
I have one week and I have not figured it out yet.
Just open both files and, in a loop, read four lines from the first and one line from the second. Output each line as it's read.
using (var outputFile = File.CreateText("OutputFile.txt"))
{
using (var input1 = File.OpenText("TryAgain.txt"))
using (var input2 = File.OpenText("File2.txt"))
{
while (!input1.EndOfStream && !input2.EndOfStream))
{
int i;
for (i = 0; i < 4 && !input1.EndOfStream; ++i))
{
var s1 = input1.ReadLine();
outputFile.WriteLine(s1);
}
if (i != 4) break; // end of first file
// now read one line from the other file, and output it
var s2 = input2.ReadLine();
outputFile.WriteLine(s2);
}
}
}
This has the advantage of not having to read both files into memory all at once, and you don't have to build the entire output in memory. Each line is output immediately after it's written.
Edit: I edit the code via Jim, he warned me and now it's working.
First you need to read both files and store all lines to string array. Then loop them like down bellow. Every fifth item you need to check and write from second file.
PS: I did not try the code but prob it will work without an error.
string[] first = System.IO.File.ReadAllLines("path of first txt file");
string[] second = System.IO.File.ReadAllLines("path of second txt file");
var sb = new StringBuilder();
var k = 0;
var m = 0;
for (int i = m; i < second.Length; i++)
{
m = i + 1;
for (int j = k; j < first.Length; j++)
{
k = j + 1;
if (j != 0 && j % 4 == 0)
{
sb.Append(second[i] + "\n");
break;
}
else
{
sb.Append(first[j] + "\n");
continue;
}
}
}
// create new txt file
var file = new System.IO.StreamWriter("path of third txt file");
file.WriteLine(sb.ToString());
Related
I read strings from text file, and among the strings there is one: "15121 ♥☺020 000000/=n531☻".
I use .Contain() method to spot ♥☺☻ symbols in the string, but it doesn't recognize them. For ♥,☺,☻ I also tried \u2665, \u263a, \u263b (as arguments for .Contain()), but none of them were recognized.
Moreover, I copied the string (from console output window) and pasted it into my code to compare symbols one by one.
string s = "15121 ♥☺020 000000/=n531☻"; // the same with "15121 \u2665\u263a020 000000/=n531\u263b"
for (int j = 0; j < s.Length; j++)
{
Console.WriteLine($"{line[j]} == {s[j]}: {line[j].Equals(s[j])}");
}
This is what I got:
What may be wrong and how do I recognize those symbols?
UPDATE: The input file I read strings from is a usual text file, and the strings inside looks like these (txt opened in Notepad):
As you can see, there is THE string among the others.
I don't use any encoding when reading the txt, and to specify how I do read the file and what the line is, here is my code:
string[] lines = File.ReadAllLines(path + target_file_name);
var list = new List<string>(lines);
for (int i = 0; i < list.Count; i++)
{
string line = list[i];
if (line.Length > 21)
{
Console.WriteLine(line);
if (line.Contains("/=n")) //used just to catch THE string
{
var line_b = Encoding.Unicode.GetBytes(line);
Console.WriteLine($"{line_b} : line = {line}");
foreach (byte m in line_b)
{
Console.Write(m + " ");
}
string s = "AAXX 15121 ♥☺020 000000/=n531☻";
Console.WriteLine();
var s_b = Encoding.Unicode.GetBytes(s);
Console.WriteLine($"{s_b} : s = {s}");
foreach (byte n in s_b)
{
Console.Write(n + " ");
}
Console.WriteLine();
for (int j = 0; j < s.Length; j++)
{
Console.WriteLine($"{line[j]} == {s[j]}: {line[j].Equals(s[j])}");
}
}
Reading all the lines from txt and converting them to List is a must for me. Thus, the line is a string line from initial txt file.
I have dumped the bytes of the inout text string var b = Encoding.Unicode.GetBytes(line); and compare with my literal (#pm100), and here is the result. Not quite sure what it does give me:
I'm sorry, I'm not willing to publish my code, and I may not understand some of your suggestions for I'm not very proficient in C# (and coding in general). So I would appreciate any further help as it is, if possible.
I am developing in C#.
I have a text file containing the following:
Sam
NYC
Mii
Peru
LEO
Argentina
I want to iterate through this file two line by two line, then print to the console the first line, second line (the Name and the Country) of each couple, so the output would be:
Sam, NYC
Mii, Peru
Here is what I have tried:
int linenum = 0;
foreach (string line in File.ReadLines("c:\\file.txt"))
{
string word = line;
string s = "";
string j = "";
linenum = linenum + 1;
if(linenum % 2 != 0) //impaire
{
s = line;
}
else
{
j = line;
}
Console.WriteLine((string.Concat(s, j));
}
But that's not working, I want to do:
int linenum = 0;
foreach( two lines in File.ReadLines("c:\\file.txt"))
{
linenum = linenum + 1;
//get the first line (linenum = 1) and store it in a string s
// then get the second line (linenum = 2) and store it in a string j
// then print the two strings together to the console like that
Console.WriteLine((string.Concat("S: " + s,"J: " j));
}
How can I do that ?
Use File.ReadAllLines to return an array of strings:
var lines = File.ReadAllLines(filePath);
for (int i = 0; i < lines.Length; i+=2)
{
var s = lines[i];
var j = lines[i+1];
Console.WriteLine($"S: {s} J: {s}");
}
You do your output with Console.WriteLine in every line, but you also should do that only for every second line. Furthermore, your variables s and j live inside the loop's scope, so they are recreated with every iteration and loose their prior value.
int i = 0; string prev = "";
foreach (string line in File.ReadLines("c:\\file.txt")) {
if (i++ % 2 == 0) prev = line;
else Console.WriteLine($"{prev}, {line}");
}
Another approach would be iterating the array you get from File.ReadAllLines with an for loop instead of foreach and increase the index by 2
var lines = File.ReadAllLines("c:\\file.txt");
//make sure, you have an even number of lines!
if (lines.Length% 2 == 0) for (int i = 0; i < lines.Length; i+=2) {
Console.WriteLine($"{lines[i]}, {lines[i+1]}");
}
You can write yourself a little helper method to return batches of lines.
This implementation handles files that are not a multiple of the batch size (2 in your case) by returning "" for the missing lines at the end of the file.
public static IEnumerable<string[]> BatchedLinesFromFile(string filename, int batchSize)
{
string[] result = Enumerable.Repeat("", batchSize).ToArray();
int count = 0;
foreach (var line in File.ReadLines(filename))
{
result[count++] = line;
if (count != batchSize)
continue;
yield return result;
count = 0;
result = Enumerable.Repeat("", batchSize).ToArray();
}
if (count > 0)
yield return result;
}
Note that this also returns a separate array for each result, in case you make a copy of it.
Given that code, you can use it like so:
foreach (var batch in BatchedLinesFromFile(filename, 2))
{
Console.WriteLine(string.Join(", ", batch));
}
Actually, you can use LINQ to get two lines in a time using Take
var twoLines = File.ReadLines(#"YourPath").Take(2));
As you can use Skip to skip the two lines you took and take the next two lines like :
var twoLines = File.ReadLines(#"YourPath").Skip(2).Take(2));
EDIT : Thanks for #derpirscher there were a performance issue so changed the code to the following :
first read the whole file and store it in a string array
then loop through it using LINQ to take two elements from the array in a time.
string[] myStringArray = File.ReadAllLines(#"YourFile.txt");
for (int i = 0; i < myStringArray.Length ; i+=2)
{
var twoLines = myStringArray.Skip(i).Take(2).ToArray();
}
Another one, using Enumerable.Repeat() and an interger selector incremented a [NumberOfLines / 2] times.
Could be interesting for the LINQ addicted (a for / foreach solution is probably better anyway).
string[] input = File.ReadAllLines([SourcePath]);
int Selector = -1;
string[] output = Enumerable.Repeat(0, input.Length / 2).Select(_ => {
Selector += 2;
return $"{input[Selector - 1]} {input[Selector]}";
}).ToArray();
The output is:
Sam NYC
Mii Peru
LEO Argentina
Use the right tool for the job. foreach() is not the right tool here.
Without giving up the memory efficiency of ReadLines() over ReadAll():
using (var lines = File.ReadLines("c:\\file.txt").GetEnumerator())
{
while (lines.MoveNext())
{
string firstLine = lines.Current;
if (!lines.MoveNext())
throw new InvalidOperationException("odd nr of lines");
string secondLine = lines.Current;
// use 2 lines
Console.WriteLine("S: " + firstLine ,"J: " + secondLine);
}
}
I have a problem with C#.
I am writing code to search a text file until it finds a certain word, then the code should move three lines and read the fourth, then continue the search to find the certain word again.
Now I don't know how to navigate through the file (forward and backward) to the line I want.
Can anybody help?
You can do something like this:
var text = File.ReadAllLines("path"); //read all lines into an array
var foundFirstTime = false;
for (int i = 0; i < text.Length; i++)
{
//Find the word the first time
if(!foundFirstTime && text[i].Contains("word"))
{
//Skip 3 lines - and continue
i = Math.Min(i+3, text.Length-1);
foundFirstTime = true;
}
if(foundFirstTime && text[i].Contains("word"))
{
//Do whatever!
}
}
// read file
List<string> query = (from lines in File.ReadLines(this.Location.FullName, System.Text.Encoding.UTF8)
select lines).ToList<string>();
for (int i = 0; i < query.Count; i++)
{
if (query[i].Contains("TextYouWant"))
{
i = i + 3;
}
}
Your requirements state that you are searching for a specific word. If that is true and you are not instead looking for a specific string, then the checked answer on this is wrong. Instead you should use:
string[] lines = System.IO.File.ReadAllLines("File.txt");
int skip = 3;
string word = "foo";
string pattern = string.Format("\\b{0}\\b", word);
for (int i = 0; i < lines.Count(); i++)
{
var match = System.Text.RegularExpressions.Regex.IsMatch(lines[i], pattern);
System.Diagnostics.Debug.Print(string.Format("Line {0}: {1}", Array.IndexOf(lines, lines[i], i) + 1, match));
if (match) i += skip;
}
If you use the string.contains method and the word you are searching for is "man", while your text somewhere contains "mantle" and "manual", the string.contains method will return as true.
I have a text file that I load into a string array. The contents of the file looks something like this:
OTI*IA*IX*NA~ REF*G1*J EVERETTE~ REF*11*0113722462~
AMT*GW*229.8~ NM1*QC*1*JENNINGS*PHILLIP~ OTI*IA*IX*NA~ REF*G1*J
EVERETTE~ REF*11*0113722463~ AMT*GW*127.75~
NM1*QC*1*JENNINGS*PHILLIP~ OTI*IA*IX*NA~ REF*G1*J EVERETTE~
REF*11*0113722462~ AMT*GW*10.99~ NM1*QC*1*JENNINGS*PHILLIP~ ...
I'm looking for the lines that start with OTI, and if it's followed by "IA" then I need to get the 10 digit number from the line that starts with REF*11. So far, I have this:
string[] readText = File.ReadAllLines("myfile.txt");
foreach (string s in readText) //string contains 1 line of text from above example
{
string[] currentline = s.Split('*');
if (currentline[0] == "OTI")
{
//move down 2 lines and grab the 10 digit
//number from the line that starts with REF*11
}
}
The line I need is always 2 lines after the current OTI line. How do I access the line that's 2 lines down from my current line?
Instead of using foreach() you can use a for(int index = 0; index < readText.Length; index++)
Then you know the line you are accessing and you can easily say int otherIndex = index + 2
string[] readText = File.ReadAllLines("myfile.txt");
for(int index = 0; index < readText.Length; index++)
{
string[] currentline = readText[index].Split('*');
if (currentline[0] == "OTI")
{
//move down 2 lines and grab the 10 digit
//number from the line that starts with REF*11
int refIndex = index + 2;
string refLine = readText[refIndex];
}
}
What about:
string[] readText = File.ReadAllLines("myfile.txt");
for (int i = 0; i < readText.Length; i++)
{
if (readText[i].StartsWith("OTI") && readText[i+2].StartsWith("REF*11")){
string number = readText[i+2].Substring("REF*11".Length, 10);
//do something
}
}
This looks like an EDI file! Ahh, EDI, the memories...
The good news is that the EDI file is delimited, just like most CSV file formats. You can use any standard CSV file library to load the EDI file into a gigantic array, and then iterate through it by position.
I published my open source CSV library here, feel free to use it if it's helpful. You can simply specify the "asterisk" as the delimiter:
https://code.google.com/p/csharp-csv-reader/
// This code assumes the file is on disk, and the first row of the file
// has the names of the columns on it
DataTable dt = CSVReader.LoadDataTable(myfilename, '*', '\"');
At this point, you can iterate through the datatable as normal.
for (int i = 0; i < dt.Rows.Count; i++) {
if (dt.Rows[i][0] == "OTI") {
Console.WriteLine("The row I want is: " + dt.Rows[i + 2][0]);
}
}
If you want to use regex to tokenize the items and create dynamic entities, here is such a pattern
string data = #"NM1*QC*1*JENNINGS*PHILLIP~
OTI*IA*IX*NA~
REF*G1*J EVERETTE~
REF*11*0113722463~
AMT*GW*127.75~
NM1*QC*1*JENNINGS*PHILLIP~
OTI*IA*IX*NA~
REF*G1*J EVERETTE~
REF*11*0113722462~
AMT*GW*10.99~
NM1*QC*1*JENNINGS*PHILLIP~";
string pattern = #"^(?<Command>\w{3})((?:\*)(?<Value>[^~*]+))+";
var lines = Regex.Matches(data, pattern, RegexOptions.Multiline)
.OfType<Match>()
.Select (mt => new
{
Op = mt.Groups["Command"].Value,
Data = mt.Groups["Value"].Captures.OfType<Capture>().Select (c => c.Value)
}
);
That produces a list of items like this which you can apply your business logic to:
Why dont you use regular expression matches using Regex.Match or Regex.Matches defined in System.Text.RegularExpressions? You can also look at string pattern matching algorithms such as the Knuth-Morris-Pratt algorithms.
string[] readText = File.ReadAllLines("myfile.txt");
foreach (string s in readText) //string contains 1 line of text from above example
{
string[] currentline = s.Split('*');
if (currentline[0] == "REF"&¤tline[1] == "11")
{
found=false;
needed=current+2;
}
}
string[] readText = File.ReadAllLines("myfile.txt");
for(int linenum = 0;linenum < readText.Length; linenum++)
{
string s = readText[linenum];
string[] currentline = s.Split('*');
if (currentline[0] == "OTI")
{
//move down 2 lines and grab the 10 digit
linenum +=2;
string refLine = readText[linenum];
//number from the line that starts with REF*11
// Extract your number here from refline
}
}
Thank guys .. this is what I came up with, but I'm also reading your answers as I KNOW I will learn something! Thanks again!
string[] readText = File.ReadAllLines("myfile.txt");
int i = 0;
foreach (string s in readText)
{
string[] currentline = s.Split('*');
if (currentline[0] == "OTI")
{
lbRecon.Items.Add(readText[i+2].Substring(8, 9));
}
i++;
}
I'm trying to move line in a text file up by one then rewrite it back to the original file, but getting error for some reason, can't seem to figure it out.
using (StreamReader reader = new StreamReader("file.txt"))
{
string line;
int Counter = 0;
while ((line = reader.ReadLine()) != null)
{
string filepath = "file.txt";
int i = 5;
string[] lines = File.ReadAllLines(filepath);
if (lines.Length >= i)
{
string tmp = lines[i];
lines[i] = lines[i-1];
lines[i-1] = tmp;
File.WriteAllLines(filepath, lines);
}
}
Counter++;
}
You are opening the file to read in this line:
using (StreamReader reader = new StreamReader("file.txt"))
At this point it is open and being used.
You then, later on have:
string[] lines = File.ReadAllLines(filepath);
Trying to read from the same file.
It is not clear what you are trying to achieve, but this will not work.
From what I can see, you don't need the reader at all.
I assume that you actually want to swap each line(?) in the file, because of this code snippet:
string tmp = lines[i];
lines[i] = lines[i-1];
lines[i-1] = tmp;
So here's an approach that should work:
String[] lines = System.IO.File.ReadAllLines(path);
List<String> result = new List<String>();
for (int l = 0; l < lines.Length; l++)
{
String thisLine = lines[l];
String nextLine = lines.Length > l+1 ? lines[l + 1] : null;
if (nextLine == null)
{
result.Add(thisLine);
}
else
{
result.Add(nextLine);
result.Add(thisLine);
l++;
}
}
System.IO.File.WriteAllLines(path, result);
Edit: Here's the slightly modified version that swaps only one line with it's previous line, since you've commented that this is your requirement:
String[] lines = System.IO.File.ReadAllLines(path);
List<String> result = new List<String>();
int swapIndex = 5;
if (swapIndex < lines.Length && swapIndex > 0)
{
for (int l = 0; l < lines.Length; l++)
{
String thisLine = lines[l];
if (swapIndex == l + 1) // next line must be swapped with this
{
String nextLine = lines[l + 1];
result.Add(nextLine);
result.Add(thisLine);
l++;
}
else
{
result.Add(thisLine);
}
}
}
System.IO.File.WriteAllLines(path, result);
Where you are trying to open the file to write it is inside a method thats already using a streamreader to open it, stream reader opens it, file writer tries to open it but cant because it is already open,
do not read and write a file at the same time
1.if the file is small, just load it, change it, and write back.
2.if the file is huge, just open another temp file for output,
the remove/delete the first file, and then rename the second file.
Instead of having:
using (StreamReader reader = new StreamReader("file.txt"))
{
...
string[] lines = File.ReadAllLines(filepath);
}
Use:
using (StreamReader reader = new StreamReader("file.txt"))
{
string line;
string[] lines = new string[20]; // 20 is the amount of lines
int counter = 0;
while((line=reader.ReadLine())!=null)
{
lines[counter] = line;
counter++;
}
}
This will read all the lines from the file and put them into 'lines'.
You can do the same with the Writing part of the code, but this way reads from the file using only 1 process. It will read all the lines then dispose and close itself.
Hope this Helps!