editing one column in the Csv File - c#

i am trying to editing only one column within my csv. however the code does not seem to affect the file. the changes im trying to make is to change to separate the 4th column data with a comma.
class Program
{
static void Main(string[] args)
{
var filePath = Path.Combine(Directory.GetCurrentDirectory(), "kaviaReport 02_08_2016.csv");
var fileContents = ReadFile(filePath);
foreach (var line in fileContents)
{
Console.WriteLine(line);
}
Console.WriteLine("Press any key to exit...");
Console.ReadKey();
}
public static IList<string> ReadFile(string fileName)
{
var results = new List<string>();
int lineCounter = 0;
string currentLine = string.Empty;
var target = File
.ReadAllLines(fileName);
while ((currentLine = fileName) != null)//while there are lines to read
{
List<string> fielded = new List<string>(currentLine.Split(','));
if (lineCounter != 0)
{
//If it's not the first line
var lineElements = currentLine.Split(',');//split your fields into an array
var replace = target[4].Replace(' ', ',');//replace the space in position 4(field 5) of your array
results.Add(replace);
//target.WriteAllLines(string.Join(",", fielded));//write the line in the new file
}
lineCounter++;
File.WriteAllLines(fileName, target);
}
return results;
}
}

The current code has some errors.
The biggest one is the assignement of currentLine to fileName. This, of course is meaningless if you want to loop over the lines. So you need a foreach over the read lines.
Then inside the loop you should use the variable lineElements to get the 5 column available after the splitting of the currentLine.
Finally the rewrite of the file goes outside the loop and should use the result list.
// Loop, but skip the first line....
foreach(string currentLine in target.Skip(1))
{
// split your line into an array of strings
var lineElements = currentLine.Split(',');
// Replace spaces with commas on the fifth column of lineElements
var replace = lineElements[4].Replace(' ', ',');
// Add the changed line to the result list
results.Add(replace);
}
// move outside the foreach loop the write of your changes
File.WriteAllLines(fileName, results.ToArray());
Something has occured to my mind while writing this code. It is not clear if you want to rewrite the CSV file with only the data in the fifth column expanded with commas or if you want to rewrite the entire line (also column 0,1,2,3,4 etc..) in this latter case you need a different code
// Replace spaces with commas on the fifth column of lineElements
// And resssign the result to the same fifth column
lineElements[4] = lineElements[4].Replace(' ', ',');
// Add the changed line to the result list putting the comma
// between the array of strings lineElements
results.Add(string.Join(",", lineElements);

while ((currentLine = fileName) != null) will set currentLine = fileName which will make the line always true and make a infinite loop
I would write it as a for loop instead of a while
public static IList<string> ReadFile(string fileName)
{
var target = File.ReadAllLines(fileName).ToList();
// i = 1 (skip first line)
for (int i = 1; i < target.Count; i++)
{
target[4] = target[4].Replace(' ', ','); //replace the space in position 4(field 5)
}
File.WriteAllLines(fileName, target);
// Uncomment the RemoveAt(0) to remove first line
// target.RemoveAt(0);
return target;
}

Related

Grab text between two lines

I was just learning and had a problem working with files.
I have a method that has two inputs, one at the beginning of the line (lineStart) I want and the other at the end of the line (lineEnd)
I need method that extract between these two numbers for me and write on file .
ex ) lineStart = 20 , lineEnd = 90, in output Must be = 21-89 line of txt file.
string[] lines = File.ReadAllLines(#"");
int lineStart = 0;
foreach (string line0 in lines)
{
lineStart++;
if (line0.IndexOf("target1") > -1)
{
Console.Write(lineStart + "\n");
}
}
int lineEnd = 0;
foreach (string line1 in lines)
{
lineEnd++;
if (line1.IndexOf("target2") > -1)
{
Console.Write(lineEnd);
}
}
// method grabText(lineStart,lineEnd){}
enter code here
It is just a line of code
string[] lines = File.ReadLines(#"").Skip(lineStart).Take(lineEnd-lineStart);
Notice also that I use ReadLines and not ReadAllLines. The first one doesn't load everything in memory.
It is not very clear what are the boundary of the lines to take but of course it is very easy to adapt the calculation
If your text file is huge, don't read it into memory. Don't look for indexes either, just process it line by line:
bool writing = false;
using var sw = File.CreateText(#"C:\some\path\to.txt");
foreach(var line in File.ReadLines(...)){ //don't use ReadAllInes, use ReadLines - it's incremental and burns little memory
if(!writing && line.Contains("target1")){
writing = true; //start writing
continue; //don't write this line
}
if(writing){
if(line.Contains("target2"))
break; //exit loop without writing this line
sw.WriteLine(line);
}
}

How to parse out all unique variables with a certain naming convention?

I have a code file and I need to find all unique objects of type TADODataSet, but they aren't defined in this 30,000 line file I have.
I wrote a console application that splits each line into individual words and adds that word to a list if it contains ADODataSet (the naming convention prefix for the objects I'm interested in) but this didn't work quite right because of how I'm splitting my lines of code.
This is all of my code:
static void Main(string[] args)
{
string file = #"C:\somePath\Form1.cs";
string output = #"C:\someOtherPath\New Text Document.txt";
List<string> datasets = new List<string>();
string[] lines = File.ReadAllLines(file);
foreach (string line in lines)
{
string[] words = line.Split(' ');
foreach (string word in words)
{
if (word.ToLower().Contains("adodataset"))
datasets.Add(word);
}
}
if (datasets.Count > 0)
{
using (StreamWriter sw = new StreamWriter(output))
{
foreach (string dataset in datasets.Distinct())
{
sw.WriteLine(dataset);
}
}
Console.WriteLine(String.Format("Wrote {0} data sets to {1}", datasets.Distinct().Count(), output));
Console.ReadKey();
}
}
But this didn't work as I hoped, and added "words" such as these:
SQLText(ADODataSetEnrollment->FieldByName("Age1")->AsString)
SQLText(ADODataSetEnrollment->FieldByName("Age2")->AsString)
SQLText(ADODataSetEnrollment->FieldByName("Age3")->AsString)
I'm only interested in ADODataSetEnrollment, so I should only have 1 entry for that variable in my output file but because that line of code doesn't contain a space it's treated as a single "word".
How can I split my lines array instead, so that way I can find unique variables?
Have you tried RegEx matching? With RegEx you can for example say
RegEx.IsMatch(word, "(?i)(?<!\w)adodataset(?!\w)")
> (?i) means ignore case (like uppercase, lower case, i think)
> (?<!\w)means not preceded by a literal (like letters, ABC..., abc... and so
> forth)
> (?!\w) means not followed by a literal RegEx.IsMatch(...)
> returns a bool value
Ended up with this as a solution:
string file = #"C:\somePath\Form1.cs";
string output = #"C:\someOtherPath\New Text Document.txt";
List<string> datasets = new List<string>();
string[] lines = File.ReadAllLines(file);
decimal i = 0;
foreach (string line in lines)
{
string[] words = line.Split(' ');
foreach (string word in words)
{
if (word.ToLower().Contains("adodataset"))
{
int start = word.ToLower().IndexOf("adodataset");
string dsWord = String.Empty;
string temp = word.Substring(start, word.Length - start);
foreach (char c in temp)
{
if (Char.IsLetter(c))
dsWord += c;
else
break;
}
if (dsWord != String.Empty)
datasets.Add(dsWord);
}
}
i++;
Console.Write("\r{0}% ", Math.Round(i / lines.Count() * 100, 2));
}
if (datasets.Count > 0)
{
using (StreamWriter sw = new StreamWriter(output))
{
foreach (string dataset in datasets.Distinct())
sw.WriteLine(dataset);
}
Console.WriteLine(String.Format("Wrote {0} data sets to {1}", datasets.Distinct().Count(), output));
Console.ReadKey();
}
Pretty ghetto, but it did what I needed it to do. I'll happily accept someone else's answer though if they know of a better way to use Regex to just pull out the variable name from within the line of code, rather than the whole line itself.
You can try this solution:
string file = File.ReadAllText(#"text.txt");
string output = #"C:\someOtherPath\New Text Document.txt";
List<string> datasets = new List<string>();
var a = Regex.Matches(file, #"\W(ADODataSet\w*)", RegexOptions.IgnoreCase);
foreach (Match m in a)
{
datasets.Add(m.Groups[1].Value);
}

SubString editing

I've tried a few different methods and none of them work correctly so I'm just looking for someone to straight out show me how to do it . I want my application to read in a file based on an OpenFileDialog.
When the file is read in I want to go through it and and run this function which uses Linq to insert the data into my DB.
objSqlCommands.sqlCommandInsertorUpdate
However I want to go through the string , counting the number of ","'s found . when the number reaches four I want to only take the characters encountered until the next "," and do this until the end of the file .. can someone show me how to do this ?
Based on the answers given here my code now looks like this
string fileText = File.ReadAllText(ofd.FileName).Replace(Environment.NewLine, ",");
int counter = 0;
int idx = 0;
List<string> foo = new List<string>();
foreach (char c in fileText.ToArray())
{
idx++;
if (c == ',')
{
counter++;
}
if (counter == 4)
{
string x = fileText.Substring(idx);
foo.Add(fileText.Substring(idx, x.IndexOf(',')));
counter = 0;
}
}
foreach (string s in foo)
{
objSqlCommands.sqlCommandInsertorUpdate("INSERT", s);//laClient[0]);
}
However I am getting an "length cannot be less than 0" error on the foo.add function call , any ideas ?
A Somewhat hacky example. You would pass this the entire text from your file as a single string.
string str = "1,2,3,4,i am some text,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20";
int counter = 0;
int idx = 0;
List<string> foo = new List<string>();
foreach (char c in str.ToArray())
{
idx++;
if (c == ',')
{
counter++;
}
if (counter == 4)
{
string x = str.Substring(idx);
foo.Add(str.Substring(idx, x.IndexOf(',')));
counter = 0;
}
}
foreach(string s in foo)
{
Console.WriteLine(s);
}
Console.Read();
Prints:
i am some text
9
13
17
As Raidri indicates in his answer, String.Split is definitely your friend. To catch every fifth word, you could try something like this (not tested):
string fileText = File.ReadAllText(OpenDialog.FileName).Replace(Environment.NewLine, ",");
string words[] = fileText.Split(',');
List<string> everFifthWord = new List<string>();
for (int i = 4; i <= words.Length - 1, i + 5)
{
everyFifthWord.Add(words[i]);
}
The above code reads the selected file from the OpenFileDialog, then replaces every newline with a ",". Then it splits the string on ",", and starting with the fifth word takes every fifth word in the string and adds it to the list.
File.ReadAllText reads a text file to a string and Split turns that string into an array seperated at the commas:
File.ReadAllText(OpenDialog.FileName).Split(',')[4]
If you have more than one line use:
File.ReadAllLines(OpenDialog.FileName).Select(l => l.Split(',')[4])
This gives an IEnumerable<string> where each string contains the wanted part from one line of the file
It's not clear to me if you're after every fifth piece of text between the commas or if there are multiple lines and you want only the fifth piece of text on each line. So I've done both.
Every fifth piece of text:
var text = "1,2,3,4,i am some text,6,7,8,9"
+ ",10,11,12,13,14,15,16,17,18,19,20";
var everyFifth =
text
.Split(',')
.Where((x, n) => n % 5 == 4);
Only the fifth piece of text on each line:
var lines = new []
{
"1,2,3,4,i am some text,6,7",
"8,9,10,11,12,13,14,15",
"16,17,18,19,20",
};
var fifthOnEachLine =
lines
.Select(x => x.Split(',')[4]);

read a specific line from a file

I am trying to get a list of lines that are before lines that contains a specific word. Here is my script:
private static void Main(string[] args)
{
int counter = 0;
string line;
System.IO.StreamReader file = new System.IO.StreamReader("E:\\overview2.srt");
List<string> lines = new List<string>();
while ((line = file.ReadLine()) != null)
{
if (line.Contains("medication"))
{
int x = counter - 1;
Console.WriteLine(x); // this will write the line number not its contents
}
counter++;
}
file.Close();
}
Using LINQ method syntax:
var lines = File.ReadLines("E:\\overview2.srt")
.Where(line => line.Contains("medication"))
.ToList();
and LINQ keyword syntax:
var lines = (
from line in File.ReadLines("E:\\overview2.srt")
where line.Contains("medication")
select line
).ToList();
If you need an array, use .ToArray() instead of .ToList().
Also, if all you need is to iterate once over the lines, don't bother with ToArray or ToList:
var query =
from line in File.ReadLines("E:\\overview2.srt")
where line.Contains("medication")
select line;
foreach (var line in query) {
Console.WriteLine(line);
}
This code will show all lines immediately before any line that contains your search text.
private static void Main(string[] args)
{
string cacheline = "";
string line;
System.IO.StreamReader file = new System.IO.StreamReader("C:\\overview2.srt");
List<string> lines = new List<string>();
while ((line = file.ReadLine()) != null)
{
if (line.Contains("medication"))
{
lines.Add(cacheline);
}
cacheline = line;
}
file.Close();
foreach (var l in lines)
{
Console.WriteLine(l);
}
}
It's difficult to tell from your question where you're looking for ALL lines before the found line or just a single line. (You would have to deal with the special case where the search text is found on the first line).
You could create a Queue<string>. Add each line to it as you pass over it. If it has more than the required number of lines in it dequeue the first item. When you hit your required search expression the Queue<string> contains all the lines you will need to output.
Or if memory is no object, you could just use File.ReadAllLines (see http://msdn.microsoft.com/en-us/library/system.io.file.readalllines.aspx) and index away into an array.
try this:
int linenum = 0;
foreach (var line in File.ReadAllLines("Your Address"))
{
if (line.Contains("medication"))
{
Console.WriteLine(string.Format("line Number:{} Text:{}"linenum,line)
//Add to your list or ...
}
linenum++;
}

C# - Read/Copy/Replace Lines In Text

I have a text file that I am opening up and it is in a similar format to this:
10 SOME TEXT
20 T A40
B B5, C45, D48
30 B E25
40 B F17, G18
60 T H20, I23,
B J6, K7, L8, M9, N10, O11, P12,
Q31, R32, S33, T34, U35, V36,
W37, X38, Y39
100 T Z65
360 B A1, B4, C5, D6, E7, F10
2000 T SOME TEXT
423 TEXT
With this text I need to be able to read it and replace values accordingly. If a ReadLine begins with a number (ie, 10, 20, 30, 40, 60, 100, 360, 2000, 423) I need to to check if there is a T, B, or text after it. The only case that I need to change/reformat the lines when they come in and output them differently.
Example: 10 is fine except for I would like to add zeros in front of every number to make them 4 digits long (ie, 10 turns to 0010, 360 turns to 0360, 2000 stays the same). When the string "B B5, C45, D48" is read (this is the third line in the text) I need to change it to say "20A B5, C45, D48". I need to grab the number above the "B" and concat it to the "B" and replace the "B" with an "A". If instead of a "B" there is a "T" I simply need to remove the "T". Also, if a line does not start with a number or a "B" (ie, Q31 or W37) I need to concat that line with the previous line.
So after the changes take place it should look like this:
0010 SOME TEXT
0020 A40
0020A B5, C45, D48
0030A E25
0040A F17, G18
0060 H20, I23,
0060A J6, K7, L8, M9, N10, O11, P12, Q31, R32, S33, T34, U35, V36, W37, X38, Y39
0100 Z65
0360A A1, B4, C5, D6, E7, F10
2000 SOME TEXT
0423 TEXT
I am currently trying to use Regex to do this but I have been told that there is an easier way to do this and I am not sure how. So far I have been able to add the zeros in front of the numbers. Also, my code is adding an "A" to the end of everything as well as keeping the original number on the next line and I am not grabbing the lines that begin with anything but a digit.
This is what my current output is turning out to look like:
0010A
0010
0020A
0020
0030A
0030
0060A
0060
0100A
0100
0360A
0360
2000
2000
0423A
0423
I am obviously doing something wrong using Regex.
Here is my current code:
private void openRefsButton_Click(object sender, EventArgs e)
{
// Initialize the OpenFileDialog to specify the .txt extension as well as
// its intial directory for the file.
openRefs.DefaultExt = "*.txt";
openRefs.Filter = ".txt Files|*.txt";
openRefs.InitialDirectory = "C:\\";
openRefs.RestoreDirectory = true;
try
{
// Open the contents of the file into the originalTextRichTextBox.
if (openRefs.ShowDialog() == DialogResult.OK && openRefs.FileName.Length > 0)
refsTextRichTextBox.LoadFile(openRefs.FileName, RichTextBoxStreamType.PlainText);
// Throws a FileNotFoundException otherwise.
else
throw new FileNotFoundException();
StreamReader refsInput = File.OpenText(openRefs.FileName);
string regExpression = #"^[\d]+";
string findNewBottomRegex = #"^B\s";
StringBuilder buildNumberText = new StringBuilder();
StringBuilder formatMatchText = new StringBuilder();
foreach (string allLines in File.ReadAllLines(openRefs.FileName))
{
Match newBottomMatch = Regex.Match(allLines, findNewBottomRegex);
Match numberStartMatch = Regex.Match(allLines, regExpression);
int counter = 0;
if (counter < numberStartMatch.Length)
{
if (numberStartMatch.Value.Length == 2)
{
if (refsTextRichTextBox.Text.Contains(newBottomMatch.ToString()))
{
finalTextRichTextBox.AppendText("00" + numberStartMatch + "A\n");
}
finalTextRichTextBox.AppendText("00" + numberStartMatch + "\n");
}
else if (numberStartMatch.Value.Length == 3)
{
if (refsTextRichTextBox.Text.Contains(newBottomMatch.ToString()))
{
finalTextRichTextBox.AppendText("0" + numberStartMatch + "A\n");
}
finalTextRichTextBox.AppendText("0" + numberStartMatch + "\n");
}
else
{
if (refsTextRichTextBox.Text.Contains(newBottomMatch.ToString()))
{
finalTextRichTextBox.AppendText(numberStartMatch + "A\n");
}
finalTextRichTextBox.AppendText(numberStartMatch + "\n");
}
counter++;
}
}
}
// Catches an exception if the file was not opened.
catch (Exception)
{
MessageBox.Show("There was not a specified file path.", "Path Not Found Error",
MessageBoxButtons.OK, MessageBoxIcon.Warning);
}
}
}
}
QUESTION(S):
What is a better way to go about doing this task?
Are there any recommendations on changing my code to be more efficient and cleaner?
How do I properly split each line into number, T/B, A40 when every line is not the same?
After the lines are properly split, how do I replace copy the line before if the current line begins with a "B"?
If the line begins with "Q31" or similar, how do I add that current line to the end of the previous one?
Once this happens, is there a way to concat everything to create the speficied format above?
WORK FLOW #jaywayco
Open Text File
Read file line by line
Save each line in a list of strings
Split each string by ' '
Find each line that starts with a digit
Replace that digit to make it 4 digits in length
Check the following text after the digit to see if it is a "B ", "T ", or "SOME TEXT"
if "B " copy the line above
Add an "A" to the end of the digit
if "T " remove the "T "
if "SOME TEXT" do nothing
Find each line that starts with a "B "
Copy the digits on the line above and concat to the front of the "B "
Follow step 4.b.i
Find each line that starts with (or similar to) "Q31"
Concat this line to the end of the previous line
...?
Here's a really lame, procedural solution:
using System.IO;
using System.Collections.Generic;
namespace ConsoleApplication
{
class Program
{
static void Main(string[] args)
{
var list = new List<string>();
using (var reader = File.OpenText(#"c:\input.txt"))
{
while (true)
{
var line = reader.ReadLine();
if (string.IsNullOrEmpty(line)) break;
list.Add(line);
}
}
list = HandleRemoveTRequirement(list);
list = HandleFourDigitRequirement(list);
list = HandleConcatRequirement(list);
list = HandleStartsWithBRequirement(list);
list = HandleSecondElementIsBRequirement(list);
using (var output = new StreamWriter(#"c:\output.txt"))
{
foreach (var line in list)
{
output.WriteLine(line);
}
}
}
static List<string> HandleSecondElementIsBRequirement(List<string> list)
{
var result = new List<string>();
foreach (var line in list)
{
var parts = line.Split(' ');
if (parts[1].Equals("B"))
{
parts[0] += "A";
parts[1] = string.Empty;
result.Add(string.Join(" ", parts).Replace(" ", " "));
}
else
{
result.Add(line);
}
}
return result;
}
static List<string> HandleStartsWithBRequirement(List<string> list)
{
var result = new List<string>();
var i = 0;
foreach (var line in list)
{
var parts = line.Split(' ');
if (parts[0].Equals("B"))
{
parts[0] = string.Empty;
result.Add(list[i - 1].Split(' ')[0] + "A" + string.Join(" ", parts));
}
else
{
result.Add(line);
}
i++;
}
return result;
}
static List<string> HandleConcatRequirement(List<string> list)
{
var result = new List<string>();
foreach (var line in list)
{
var parts = line.Split(' ');
int test;
if (int.TryParse(parts[0], out test) || parts[0].Equals("B"))
{
result.Add(line);
}
else
{
result[result.Count -1] += line;
}
}
return result;
}
static List<string> HandleRemoveTRequirement(List<string> list)
{
var result = new List<string>();
foreach (var line in list)
{
var parts = line.Split(' ');
if (parts[1].Equals("T"))
{
parts[1] = string.Empty;
}
result.Add(string.Join(" ", parts).Replace(" ", " "));
}
return result;
}
static List<string> HandleFourDigitRequirement(List<string> list)
{
var result = new List<string>();
foreach (var line in list)
{
var parts = line.Split(' ');
int test;
if (int.TryParse(parts[0], out test))
{
parts[0] = parts[0].PadLeft(4, '0');
result.Add(string.Join(" ", parts));
}
else
{
result.Add(line);
}
}
return result;
}
}
}
These are pretty complicated requirements and I would be tempted to implement this as a workflow. This way you can separate out each of the logical steps and this will increase maintainability.
I would be tempted to represent the text file as an array of string arrays or even a data table. Then you can write general functions that concatenate/transform specific values
One way to possibly approach this is similiar to jaywayco's.
I'd start with placing each line split by spaces into it's own array. Place that array into an Array of arrays. From there you can consider your workflow. Your line array that is split by the spaces you can determine how to print it based off the first value, being a number or letter B etc... If it's a B, you know that it should start with array[i-1] first value, which would be the number etc. You'd have to think through the logic a bit, but I think you can understand where I am coming from. I'm not sure if this is the best approach or not, but I think this is the way I would tackle it. Good luck!
Edit: Here is some mock code...
var mainArray = new Array[textFile.Count];
//obviously get the count of number of lines set that to the size of your array object.
for(int i=0; i < mainArray.Length; i++)
{
var line = methodToGetLineFromTextFile[i];
string[] lineArray = line.Split(' ');
mainArray[i] = lineArray;
}
//Once you have everything loaded into your arrays, apply your workflow logic.
Hope this helps!
The way I would go about this task is to write a set of unit tests based on your requirements, then make them pass one at a time (having one test per requirement).
As jaywayco suggested, I would read the file into an array of lines, then implement each of your rules as a line transformation method which can be tested in isolation. I would probably separate out the method which can select which transformation(s) to apply. Then loop over the lines and apply the transformations.

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