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Can someone please confirm the reason behind foreach loop giving error as "invalid token" and "splittedText" as does not exist in current context?

string[] splittedText = File.ReadAllLines(#"file.txt");//.Split(',');
foreach (string data in splittedText)
{
}
I want to read through a file in c# which returns array of string type. Then, I will be iterating over the array to fetch my desired data.

If you want to read a CSV file, you should use a CVS parser. Values in the CSV file are separated using command and in some cases, the value in the CSV file can also contain a comma. In that case, the column values are wrapped in double-quotes. And this solution will not handle that scenario.
var splittedText = File.ReadAllText("E:\\Test.txt").Split(',');
foreach (string data in splittedText)
{
Console.WriteLine(data.Trim());
}

Hint - Reading file line by line or Reading whole file content depends on your use case. May be below code snippet give some idea on how to split the content.
Please try.
var inputtext = File.ReadAllText(#"inpufile.txt");
inputtext.Replace("\n", "")
.Split(',',
StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries)
.ToList().ForEach(t =>
{
System.Console.WriteLine(t);
//Other manupulations
});
if you want to split based on multiple characters , pass a character array to the split().
new char[] { ',', ':' };
Thank you.

You need change File.ReadAllLines to File.ReadAllText(path) then you can split method.

C# text file to string array and how to remove specific strings?

I need read a text file (10mb) and convert to .csv. See below portion of code:
string DirPathForm = System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetEntryAssembly().Location);'
string[] lines = File.ReadAllLines(DirPathForm + #"\file.txt");
Some portion of the text file have a pattern. So, used as below:
string[] lines1 = lines.Select(x => x.Replace("abc[", "ab,")).ToArray();
Array.Clear(lines, 0, lines.Length);
lines = lines1.Select(x => x.Replace("] CDE ", ",")).ToArray();
Some portion does not have a pattern to use directly Replace. The question is how remove the characters, numbers and whitespaces in this portion. Please see below?
string[] lines = {
"a] 773 b",
"e] 1597 t",
"z] 0 c"
};
to get the result below:
string[] result = {
"a,b",
"e,t",
"z,c"
};
obs: the items removed need be replaced by ",".

First of all, you should not use ReadAllLines since it is a huge file operation. It will load all the data into RAM and it is not correct. Instead, read the lines one by one in a loop.
Secondly, you can definitely use regex to replace data from the first condition to the second one.

Reading from a string List<>

my application basically reads a CSV file which will always have the same format and I need to application to create a CSV file with different formatting. Reading and writing CSV file is not the issue, however the problem I am having is reading from the string array containing all the data from the CSV file.
For example: From the below, how can I get the system to get me the 4th value only: Value Date
[0] = "\"Book Date\",\"Reference\",\"Descript\",\"Value Date\",\"Debit\",\"Credit\",\"Closing Balance\""
This is how I am reading from CSV file.
openFileDialog1.ShowDialog();
var reader = new StreamReader(File.OpenRead(openFileDialog1.FileName));
List<string> searchList = new List<string>();
while (!reader.EndOfStream)
{
var line = reader.ReadLine();
searchList.Add(line);
}

Use String.Split. It returns a string array that contains the substrings in this instance that are delimited by elements of a specified string or Unicode character array.
var splitStrings = line.Split(",");
if (splitStrings.Length > 4)
{
searchList.Add(splitStrings[3]);
}

split the line and get the 4th value like this:
searchList.Add(line.Split(',')[3]);

CSV change delimiter

i'm reading a CSV file and changing the delimiter from a "," to a "|". However i've noticed in my data (which I have no control over) that in certain cases I have some data that does not want to follow this rule and it contains quoted data with a comma in it. I'm wondering how best to not replace these exceptions?
For example:
ABSON TE,Wick Lane,"Abson, Pucklechurch",Bristol,Avon,ENGLAND,BS16
9SD,37030,17563,BS0001A1,,
Should be changed to:
ABSON TE|Wick Lane|"Abson, Pucklechurch"|Bristol|Avon|ENGLAND|BS16
9SD|37030|17563|BS0001A1||
The code to read and replace the CSV file is this:
var contents = File.ReadAllText(filePath).Split(new string[] { "\n", "\r\n" }, StringSplitOptions.RemoveEmptyEntries).ToArray();
var formattedContents = contents.Select(line => line.Replace(',', '|'));

For anyone else struggling with this, I ended up using the built in .net csv parser. See here for more details and example: http://coding.abel.nu/2012/06/built-in-net-csv-parser/
My specific code:
// Create new parser object and setup parameters
var parser = new TextFieldParser(new StringReader(File.ReadAllText(filePath)))
{
HasFieldsEnclosedInQuotes = true,
Delimiters = new string[] { "," },
TrimWhiteSpace = true
};
var csvSplitList = new List<string>();
// Reads all fields on the current line of the CSV file and returns as a string array
// Joins each field together with new delimiter "|"
while (!parser.EndOfData)
{
csvSplitList.Add(String.Join("|", parser.ReadFields()));
}
// Newline characters added to each line and flattens List<string> into single string
var formattedCsvToSave = String.Join(Environment.NewLine, csvSplitList.Select(x => x));
// Write single string to file
File.WriteAllText(filePathFormatted, formattedCsvToSave);
parser.Close();

Processing CSV file using C#

I am creating a CSV Importing tool (comma separated). I am trying to make this importing tool as generic as possible , so that it can process any CSV File.
I have almost finalised the tool , but came across one file which I am finding it difficult to process.
How can I process the file with data in following format?
column1,column2,column3,column4,column5
----------
alex,p,22323,23232,hello
mike,t,"121212,232323,4343434",33432,hi
guna,s,"2423,2332",whats
cena,a,34443,33432,up
Since the file is comma separated, and one of its value is comma separated as well between identifier "value,value,value" I am finding it difficult to process.
How can i tackle this issue?
I donot have control over CSV file. So I cant change the format

As per #dtb... use a CSV parser. If you reference Microsoft.VisualBasic then you can:
var data=#"column1,column2,column3,column4,column5
----------
alex,p,22323,23232,hello
mike,t,""121212,232323,4343434"",33432,hi
guna,s,""2423,2332"",whats
cena,a,34443,33432,up";
using (var sr = new StringReader(data))
using (var parser =
new TextFieldParser(sr)
{
TextFieldType = FieldType.Delimited,
Delimiters = new[] { "," },
CommentTokens = new[] { "--" }
})
{
while (!parser.EndOfData)
{
string[] fields;
fields = parser.ReadFields();
//yummy
}
}
This deals with quotes correctly.