We Keep Coding

Determine whether each character in the first string can be uniquely replaced by a character in the second string so that the two strings are equal

Give two strings of equal size. Determine whether each character in the first string can be uniquely replaced by a character in the second string so that the two strings are equal. Display also the corresponding character pairs between the two strings. The code works well now.
Example 1:
For input data:
aab
ttd
The console will display:
True
a => t
b => d
Example 2:
For input data:
tab
ttd
The console will display:
False
In the second example the answer is false because there is no unique correspondence for the character 'a': both 't' and 'd' correspond to it.
This is my code:
using System;
namespace problemeJM
{
class Program
{
static void Main(string[] args)
{
string firstPhrase = Convert.ToString(Console.ReadLine());
string secondPhrase = Convert.ToString(Console.ReadLine());
string aux1 = string.Empty, aux2 = string.Empty;
bool x = true;
for (int i = 0; i < firstPhrase.Length; i++)
{
if (!aux1.Contains(firstPhrase[i]))
{
aux1 += firstPhrase[i];
}
}
for (int i = 0; i < secondPhrase.Length; i++)
{
if (!aux2.Contains(secondPhrase[i]))
{
aux2 += secondPhrase[i];
}
}
if (aux1.Length != aux2.Length)
{
Console.WriteLine("False");
}
else
{
for (int i = 0; i < firstPhrase.Length - 2; i++)
{
for (int j = 1; j < secondPhrase.Length - 1; j++)
{
if (firstPhrase[i] == firstPhrase[j] && secondPhrase[i] == secondPhrase[j])
{
x = true;
}
else if (firstPhrase[i] != firstPhrase[j] && secondPhrase[i] != secondPhrase[j])
{
x = true;
}
else if (firstPhrase[i] == firstPhrase[j] && secondPhrase[i] != secondPhrase[j])
{
x = false;
break;
}
else if (firstPhrase[i] != firstPhrase[j] && secondPhrase[i] == secondPhrase[j])
{
x = false;
break;
}
}
}
Console.WriteLine(x);
aux1 = string.Empty;
aux2 = string.Empty;
if (x == true)
{
for (int i = 0; i < firstPhrase.Length; i++)
{
if (!aux1.Contains(firstPhrase[i]))
{
aux1 += firstPhrase[i];
}
}
for (int i = 0; i < secondPhrase.Length; i++)
{
if (!aux2.Contains(secondPhrase[i]))
{
aux2 += secondPhrase[i];
}
}
for (int i = 0; i <= aux1.Length - 1; i++)
{
for (int j = 1; j <= aux2.Length; j++)
{
if (aux1[i] == aux1[j] && aux2[i] == aux2[j])
{
Console.WriteLine(aux1[i] + " => " + aux2[i]);
break;
}
else if (aux1[i] != aux1[j] && aux2[i] != aux2[j])
{
Console.WriteLine(aux1[i] + " => " + aux2[i]);
break;
}
}
}
}
}
}
}
}

I think you should use a Dictionary<char, char> as commented. But you need to check if there's a unique mapping in both string, so from s1 to s2 and from s2 to s1:
static bool UniqueMapping(string s1, string s2)
{
int length = Math.Min(s1.Length, s2.Length);
var dict = new Dictionary<char, char>(length);
for (int i = 0; i < length; i++)
{
char c1 = s1[i];
char c2 = s2[i];
bool contained = dict.TryGetValue(c1, out char c);
if (contained && c2 != c)
{
return false;
}
dict[c1] = c2;
}
return true;
}
Here are your samples. Note that i use UniqueMapping twice(if true after 1st):
static void Main(string[] args)
{
var items = new List<string[]> { new[]{ "aab", "ttd" }, new[] { "tab", "ttd" }, new[] { "ala bala portocala", "cuc dcuc efghficuc" }, new[] { "ala bala portocala", "cuc dcuc efghijcuc" } };
foreach (string[] item in items)
{
bool result = UniqueMapping(item[0], item[1]);
if(result) result = UniqueMapping(item[1], item[0]);
Console.WriteLine($"Word 1 <{item[0]}> Word 2 <{item[1]}> UniqueMapping? {result}");
}
}
.NET Fiddle: https://dotnetfiddle.net/4DtIyH

Index was outside the bounds of the array?

I keep getting this message "System.IndexOutOfRangeException: Index was outside the bounds of the array." when attempting to run a program I built, that utilized an exception catcher.
class StudentS
{
private List theStudentList;
public bool PopulateStudents(string path)
{
theStudentList = new List<Student>();
bool flag = false;
try
{
List<string[]> strArrayList = new List<string[]>();
using (StreamReader streamReader = new StreamReader(path))
{
string str;
while ((str = streamReader.ReadLine()) != null)
{
string[] strArray = str.Split(',');
strArrayList.Add(strArray);
}
}
for (int index1 = 0; index1 < strArrayList.Count; ++index1)
{
string[] strArray = strArrayList[index1];
Student student = new Student(strArray[0], strArray[1], strArray[2]); **where the error is**
int index2 = 3;
while (index2 < strArray.Length)
{
student.EnterGrade(int.Parse(strArray[index2]), int.Parse(strArray[index2 + 1]));
index2 += 2;
}
student.CalGrade();
theStudentList.Add(student);
}
}
catch (Exception e)
{
flag = true;
Console.WriteLine(e);
}
return flag;
}
public int ListLength
{
get
{
return theStudentList.Count;
}
}
public float StudentAverage(int index)
{
return theStudentList.ElementAt(index).Average;
}
public string StudentGrade(int index)
{
return theStudentList.ElementAt(index).LetterGrade;
}
public string StudentID(int index)
{
return theStudentList.ElementAt(index).ID;
}
public string StudentLastName(int index)
{
return theStudentList.ElementAt(index).NameLast;
}
}
class Student
{
private float average;
private ArrayList Earned;
private string letterGrade;
private string nameFirst;
private string nameLast;
private ArrayList Possible;
private string studentID;
public Student(string id)
{
studentID = null;
nameFirst = null;
nameLast = null;
Earned = new ArrayList();
Possible = new ArrayList();
}
public Student(string id, string first)
{
studentID = id;
nameFirst = null;
nameLast = null;
Earned = new ArrayList();
Possible = new ArrayList();
}
public Student(string id, string first, string last)
{
nameFirst = first;
nameLast = last;
studentID = id;
Earned = new ArrayList();
Possible = new ArrayList();
}
public float Average
{
get
{
return average;
}
}
public string ID
{
get
{
return studentID;
}
}
public string LetterGrade
{
get
{
return letterGrade;
}
}
public string NameFirst
{
get
{
return nameFirst;
}
set
{
nameFirst = value;
}
}
public string NameLast
{
get
{
return nameLast;
}
set
{
nameLast = value;
}
}
public void CalGrade()
{
int num1 = 0;
int num2 = 0;
foreach (int num3 in Earned)
num1 += num3;
foreach (int num3 in Possible)
num2 += num3;
average = num1 / (float)num2;
average = (float)Math.Round(average, 2);
if (average >= 0.9)
letterGrade = "A";
if (average >= 0.8 && average < 0.9)
letterGrade = "B";
if (average >= 0.7 && average < 0.8)
letterGrade = "C";
if (average >= 0.6 && average < 0.7)
letterGrade = "D";
if (average >= 0.6)
return;
letterGrade = "U";
}
public void EnterGrade(int earnedValue, int possValue)
{
Earned.Add(earnedValue);
Possible.Add(possValue);
}
}
I am unsure as to what I have done wrong. Thanks for any help!
Edit: I went ahead and added a majority of the code here, in hopes that this answers your questions better. The data set I am dealing with is 4 rows, that are grabbed into the student array.

index2 + 1 may be out of range in the expression strArray[index2 + 1] below:
while (index2 < strArray.Length)
{
student.EnterGrade(int.Parse(strArray[index2]), int.Parse(strArray[index2 + 1]));
index2 += 2;
}
To process two elements at a time, use index2 < strArray.Length - 1

You may have a problem if the file from your path has an empty row as last row.
You access strArray[0], strArray[1], strArray[2] no matter if it is an empty array or not.

Maybe you are missing an Array.resize(). // This worked for me
Array.Resize<string[]>(ref strArrayList , count+ 1); // Count is the current length of strArrayList

Flagged the two spots where you could run into trouble:
public bool PopulateStudents(string path)
{
theStudentList = new List<Student>();
bool flag = false;
try
{
List<string[]> strArrayList = new List<string[]>();
using (StreamReader streamReader = new StreamReader(path))
{
string str;
while ((str = streamReader.ReadLine()) != null)
{
string[] strArray = str.Split(',');
strArrayList.Add(strArray);
}
}
for (int index1 = 0; index1 < strArrayList.Count; ++index1)
{
string[] strArray = strArrayList[index1];
// below that, what makes you believe strArray's length is >= 3 ?
Student student = new Student(strArray[0], strArray[1], strArray[2]);
int index2 = 3;
while (index2 < strArray.Length)
{
// here index2 will be < strArray.Length, but index2+1 might be ==
student.EnterGrade(int.Parse(strArray[index2]), int.Parse(strArray[index2 + 1]));
index2 += 2;
}
student.CalGrade();
theStudentList.Add(student);
}
}
catch (Exception e)
{
flag = true;
Console.WriteLine(e);
}
return flag;
}
Note that your while loop could be replaced with:
for(int index2 = 3; index2 < strArray.Length - 1; index2 += 2)
{
student.EnterGrade(...);
}

This is difficult to diagnose because you provided limited information. If I could see the file you are running through your program, fed in as path, I would be able to compare what the function is attempting to do to the data it is trying to do it on. That said, this looks familiar to me so I will give solving it a try and at least give you a tool to try on it.
I experienced a similar issue with a program that needed to read a CSV file for a graphics program. The problem was that when the CSV file was created, an empty line was left at the end. This left me with an empty array to represent the last line in the file.
Also, have you verified that the arrays that are added to strArrayList are consistently sized?
If you check for this empty line at the end of your file and it does not exist and if you check for commas left at the end of the lines in your file passed in as path then you can try the edits I made above to get an idea of which line(s) in your CSV file is causing the problem. I commented all the edits I made with “EDIT:” so they would be easy to find. Without more information, I cannot fix the problem, but I can maybe help you look in the right direction.
The edited code with the output for line numbers in your file which are associated with errors is below. Good luck!
public bool PopulateStudents(string path)
{
theStudentList = new List<Student>();
bool flag = false;
// EDIT: NEW VARIABLE int lineCounter declared and initialized before try block so it remains in scope when the catch block is called
int counter = 0;
try
{
List<string[]> strArrayList = new List<string[]>();
using (StreamReader streamReader = new StreamReader(path))
{
string str;
while ((str = streamReader.ReadLine()) != null)
{
string[] strArray = str.Split(',');
strArrayList.Add(strArray);
}
}
for (int index1 = 0; index1 < strArrayList.Count; ++index1)
{
// EDIT: UPDATE lineCounter
++lineCounter;
string[] strArray = strArrayList[index1];
Student student = new Student(strArray[0], strArray[1], strArray[2]);
int index2 = 3;
while (index2 < strArray.Length)
{
student.EnterGrade(int.Parse(strArray[index2]), int.Parse(strArray[index2 + 1]));
index2 += 2;
}
student.CalGrade();
theStudentList.Add(student);
}
}
catch (Exception e)
{
flag = true;
Console.WriteLine(e);
// EDIT: PRINT CURRENT LINE
Console.WriteLine(“error at line in file = “ + lineCounter);
}
return flag;
}

search in txt file and put the result in text box

i have a text file like that :
; "one"
id_number:*=344E6F4D6F7265486178785454332100
; "two"
id_number:*=3536336A775E3825246E773543563437
; "three"
id:_number*=BDBD2EB72D82473DBE09F1B552A8983
and lots the same way and what i want to search in the file for the the title (two) and after that it's give me the id_number of it and i want to put the id_number in textbox
i used
string[] s = File.ReadAllLines("MyFilePath.txt");
List<byte[]> byteArrays = new List<byte[]>();
foreach (string st in s.Where(x => x.Trim().StartsWith("id_number:*=")).Select(x => x.Skip(12)))
{
byte[] b = new byte[(int)((st.Length + 1) / 2)];
for (int i = 0; i < (int)((st.Length + 1) / 2); i++)
{
var byteString = (st.Skip(2 * i).length > 2) ? st.Skip(2 * i).Take(2) : "0" + st.Skip(2 * i);
var bt = Convert.ToByte(byteString, 16);
b[i] = bt;
}
byteArrays.Add(b);
but it doesn't work

const string f = #"C:\test.txt";
static void Main(string[] args)
{
// 1
// Declare new List.
List<string> lines = new List<string>();
// 2
// Use using StreamReader for disposing.
using (StreamReader r = new StreamReader(f))
{
// 3
// Use while != null pattern for loop
string line;
while ((line = r.ReadLine()) != null)
{
// 4
// Insert logic here.
// ...
// "line" is a line in the file. Add it to our List.
if (line.Trim() == "")
continue;
lines.Add(line);
}
}
// 5
string stringValue = "two";
int correctIndex = -1;
// Print out all the lines.
for (int i=0; i<lines.Count; i++)
{
if (lines[i].Contains(stringValue))
{
correctIndex = i;
}
}
if(correctIndex == -1)
{
Console.WriteLine("item is not found");
}
else
{
//here you will need probably little more cleaning of the string. If the strings are on 1 line you should search for lines[correctIndex]
Console.WriteLine(lines[correctIndex + 1]);
}
}
}
EDIT: I don't see your edit, check if my solution helps you. Write me a comment if you want to continue with your solution.
Here this should work. Hope this helps you.

string s, result;
bool bl = false;
using (StreamReader sr = new StreamReader("....txt"))
{
while ((s = sr.ReadLine()) != null)
{
if(s.Contains ("two"))
{
bl = true;
}
if (s.Contains("id_number") && bl == true)
{
result = s.Replace("id_number:*=", "");
textBox1.Text = result;
break;
}
}
}

Changing commas within quotes

I am trying to read the data in a text file which is separated by commas. My problem, is that one of my data pieces has a comma within it. An example of what the text file looks like is:
a, b, "c, d", e, f.
I want to be able to take the comma between c and d and change it to a semicolon so that I can still use the string.Split() method.
using (StreamReader reader = new StreamReader("file.txt"))
{
string line;
while ((line = reader.ReadLine ()) != null) {
bool firstQuote = false;
for (int i = 0; i < line.Length; i++)
{
if (line [i] == '"' )
{
firstQuote = true;
}
else if (firstQuote == true)
{
if (line [i] == '"')
{
break;
}
if ((line [i] == ','))
{
line = line.Substring (0, i) + ";" + line.Substring (i + 1, (line.Length - 1) - i);
}
}
}
Console.WriteLine (line);
}
I am having a problem. Instead of producing
a, b, "c; d", e, f
it is producing
a, b, "c; d"; e; f
It is replacing all of the following commas with semicolons instead of just the comma in the quotes. Can anybody help me fix my existing code?

Basically if you find a closing " you recognize it as it was an opening quote.
Change the line:
firstQuote = true;
to
firstQuote = !firstQuote;
and it should work.

You need to reset firstquote to false after you hit the second quote.
else if (firstQuote == true) {
if (line [i] == '"') {
firstquote = false;
break;
}

Here is a simple application to get the required result
static void Main(string[] args)
{
String str = "a,b,\"c,d\",e,f,\"g,h\",i,j,k,l,\"m,n,o\"";
int firstQuoteIndex = 0;
int secodQuoteIndex = 0;
Console.WriteLine(str);
bool iteration = false;
//String manipulation
//if count is even then count/2 is the number of pairs of double quotes we are having
//so we have to traverse count/2 times.
int count = str.Count(s => s.Equals('"'));
if (count >= 2)
{
firstQuoteIndex = str.IndexOf("\"");
for (int i = 0; i < count / 2; i++)
{
if (iteration)
{
firstQuoteIndex = str.IndexOf("\"", firstQuoteIndex + 1);
}
secodQuoteIndex = str.IndexOf("\"", firstQuoteIndex + 1);
string temp = str.Substring(firstQuoteIndex + 1, secodQuoteIndex - (firstQuoteIndex + 1));
firstQuoteIndex = secodQuoteIndex + 1;
if (count / 2 > 1)
iteration = true;
string temp2= temp.Replace(',', ';');
str = str.Replace(temp, temp2);
Console.WriteLine(temp);
}
}
Console.WriteLine(str);
Console.ReadLine();
}
Please feel free to ask in case of doubt

string line = "a,b,mc,dm,e,f,mk,lm,g,h";
string result =replacestr(line, 'm', ',', ';');
public string replacestr(string line,char seperator,char oldchr,char newchr)
{
int cnt = 0;
StringBuilder b = new StringBuilder();
foreach (char chr in line)
{
if (cnt == 1 && chr == seperator)
{
b[b.ToString().LastIndexOf(oldchr)] = newchr;
b.Append(chr);
cnt = 0;
}
else
{
if (chr == seperator)
cnt = 1;
b.Append(chr);
}
}
return b.ToString();
}

Splitting Comma Separated Values (CSV)

How to split the CSV file in c sharp? And how to display this?

I've been using the TextFieldParser Class in the Microsoft.VisualBasic.FileIO namespace for a C# project I'm working on. It will handle complications such as embedded commas or fields that are enclosed in quotes etc. It returns a string[] and, in addition to CSV files, can also be used for parsing just about any type of structured text file.

Display where? About splitting, the best way is to use a good library to that effect.
This library is pretty good, I can recommend it heartily.
The problems using naïve methods is that the usually fail, there are tons of considerations without even thinking about performance:
What if the text contains commas
Support for the many existing formats (separated by semicolon, or text surrounded by quotes, or single quotes, etc.)
and many others

Import Micorosoft.VisualBasic as a reference (I know, its not that bad) and use Microsoft.VisualBasic.FileIO.TextFieldParser - this handles CSV files very well, and can be used in any .Net language.

read the file one line at a time, then ...
foreach (String line in line.Split(new char[] { ',' }))
Console.WriteLine(line);

This is a CSV parser I use on occasion.
Usage: (dgvMyView is a datagrid type.)
CSVReader reader = new CSVReader("C:\MyFile.txt");
reader.DisplayResults(dgvMyView);
Class:
using System.IO;
using System.Text.RegularExpressions;
using System.Windows.Forms;
public class CSVReader
{
private const string ESCAPE_SPLIT_REGEX = "({1}[^{1}]*{1})*(?<Separator>{0})({1}[^{1}]*{1})*";
private string[] FieldNames;
private List<string[]> Records;
private int ReadIndex;
public CSVReader(string File)
{
Records = new List<string[]>();
string[] Record = null;
StreamReader Reader = new StreamReader(File);
int Index = 0;
bool BlankRecord = true;
FieldNames = GetEscapedSVs(Reader.ReadLine());
while (!Reader.EndOfStream)
{
Record = GetEscapedSVs(Reader.ReadLine());
BlankRecord = true;
for (Index = 0; Index <= Record.Length - 1; Index++)
{
if (!string.IsNullOrEmpty(Record[Index])) BlankRecord = false;
}
if (!BlankRecord) Records.Add(Record);
}
ReadIndex = -1;
Reader.Close();
}
private string[] GetEscapedSVs(string Data)
{
return GetEscapedSVs(Data, ",", "\"");
}
private string[] GetEscapedSVs(string Data, string Separator, string Escape)
{
string[] Result = null;
int Index = 0;
int PriorMatchIndex = 0;
MatchCollection Matches = Regex.Matches(Data, string.Format(ESCAPE_SPLIT_REGEX, Separator, Escape));
Result = new string[Matches.Count];
for (Index = 0; Index <= Result.Length - 2; Index++)
{
Result[Index] = Data.Substring(PriorMatchIndex, Matches[Index].Groups["Separator"].Index - PriorMatchIndex);
PriorMatchIndex = Matches[Index].Groups["Separator"].Index + Separator.Length;
}
Result[Result.Length - 1] = Data.Substring(PriorMatchIndex);
for (Index = 0; Index <= Result.Length - 1; Index++)
{
if (Regex.IsMatch(Result[Index], string.Format("^{0}[^{0}].*[^{0}]{0}$", Escape))) Result[Index] = Result[Index].Substring(1, Result[Index].Length - 2);
Result[Index] = Result[Index].Replace(Escape + Escape, Escape);
if (Result[Index] == null) Result[Index] = "";
}
return Result;
}
public int FieldCount
{
get { return FieldNames.Length; }
}
public string GetString(int Index)
{
return Records[ReadIndex][Index];
}
public string GetName(int Index)
{
return FieldNames[Index];
}
public bool Read()
{
ReadIndex = ReadIndex + 1;
return ReadIndex < Records.Count;
}
public void DisplayResults(DataGridView DataView)
{
DataGridViewColumn col = default(DataGridViewColumn);
DataGridViewRow row = default(DataGridViewRow);
DataGridViewCell cell = default(DataGridViewCell);
DataGridViewColumnHeaderCell header = default(DataGridViewColumnHeaderCell);
int Index = 0;
ReadIndex = -1;
DataView.Rows.Clear();
DataView.Columns.Clear();
for (Index = 0; Index <= FieldCount - 1; Index++)
{
col = new DataGridViewColumn();
col.CellTemplate = new DataGridViewTextBoxCell();
header = new DataGridViewColumnHeaderCell();
header.Value = GetName(Index);
col.HeaderCell = header;
DataView.Columns.Add(col);
}
while (Read())
{
row = new DataGridViewRow();
for (Index = 0; Index <= FieldCount - 1; Index++)
{
cell = new DataGridViewTextBoxCell();
cell.Value = GetString(Index).ToString();
row.Cells.Add(cell);
}
DataView.Rows.Add(row);
}
}
}

I had got the result for my query. its like simple like i had read a file using io.file. and all the text are stored into a string. After that i splitted with a seperator. The code is shown below.
using System;
using System.Collections.Generic;
using System.Text;
namespace CSV
{
class Program
{
static void Main(string[] args)
{
string csv = "user1, user2, user3,user4,user5";
string[] split = csv.Split(new char[] {',',' '});
foreach(string s in split)
{
if (s.Trim() != "")
Console.WriteLine(s);
}
Console.ReadLine();
}
}
}

The following function takes a line from a CSV file and splits it into a List<string>.
Arguments:
string line = the line to split
string textQualifier = what (if any) text qualifier (i.e. "" or "\"" or "'")
char delim = the field delimiter (i.e. ',' or ';' or '|' or '\t')
int colCount = the expected number of fields (0 means don't check)
Example usage:
List<string> fields = SplitLine(line, "\"", ',', 5);
// or
List<string> fields = SplitLine(line, "'", '|', 10);
// or
List<string> fields = SplitLine(line, "", '\t', 0);
Function:
private List<string> SplitLine(string line, string textQualifier, char delim, int colCount)
{
List<string> fields = new List<string>();
string origLine = line;
char textQual = '"';
bool hasTextQual = false;
if (!String.IsNullOrEmpty(textQualifier))
{
hasTextQual = true;
textQual = textQualifier[0];
}
if (hasTextQual)
{
while (!String.IsNullOrEmpty(line))
{
if (line[0] == textQual) // field is text qualified so look for next unqualified delimiter
{
int fieldLen = 1;
while (true)
{
if (line.Length == 2) // must be final field (zero length)
{
fieldLen = 2;
break;
}
else if (fieldLen + 1 >= line.Length) // must be final field
{
fieldLen += 1;
break;
}
else if (line[fieldLen] == textQual && line[fieldLen + 1] == textQual) // escaped text qualifier
{
fieldLen += 2;
}
else if (line[fieldLen] == textQual && line[fieldLen + 1] == delim) // must be end of field
{
fieldLen += 1;
break;
}
else // not a delimiter
{
fieldLen += 1;
}
}
string escapedQual = textQual.ToString() + textQual.ToString();
fields.Add(line.Substring(1, fieldLen - 2).Replace(escapedQual, textQual.ToString())); // replace escaped qualifiers
if (line.Length >= fieldLen + 1)
{
line = line.Substring(fieldLen + 1);
if (line == "") // blank final field
{
fields.Add("");
}
}
else
{
line = "";
}
}
else // field is not text qualified
{
int fieldLen = line.IndexOf(delim);
if (fieldLen != -1) // check next delimiter position
{
fields.Add(line.Substring(0, fieldLen));
line = line.Substring(fieldLen + 1);
if (line == "") // final field must be blank
{
fields.Add("");
}
}
else // must be last field
{
fields.Add(line);
line = "";
}
}
}
}
else // if there is no text qualifier, then use existing split function
{
fields.AddRange(line.Split(delim));
}
if (colCount > 0 && colCount != fields.Count) // count doesn't match expected so throw exception
{
throw new Exception("Field count was:" + fields.Count.ToString() + ", expected:" + colCount.ToString() + ". Line:" + origLine);
}
return fields;
}

Problem: Convert a comma separated string into an array where commas in "quoted strings,,," should not be considered as separators but as part of an entry
Input:
String: First,"Second","Even,With,Commas",,Normal,"Sentence,with ""different"" problems",3,4,5
Output:
String-Array: ['First','Second','Even,With,Commas','','Normal','Sentence,with "different" problems','3','4','5']
Code:
string sLine;
sLine = "First,\"Second\",\"Even,With,Commas\",,Normal,\"Sentence,with \"\"different\"\" problems\",3,4,5";
// 1. Split line by separator; do not split if separator is within quotes
string Separator = ",";
string Escape = '"'.ToString();
MatchCollection Matches = Regex.Matches(sLine,
string.Format("({1}[^{1}]*{1})*(?<Separator>{0})({1}[^{1}]*{1})*", Separator, Escape));
string[] asColumns = new string[Matches.Count + 1];
int PriorMatchIndex = 0;
for (int Index = 0; Index <= asColumns.Length - 2; Index++)
{
asColumns[Index] = sLine.Substring(PriorMatchIndex, Matches[Index].Groups["Separator"].Index - PriorMatchIndex);
PriorMatchIndex = Matches[Index].Groups["Separator"].Index + Separator.Length;
}
asColumns[asColumns.Length - 1] = sLine.Substring(PriorMatchIndex);
// 2. Remove quotes
for (int Index = 0; Index <= asColumns.Length - 1; Index++)
{
if (Regex.IsMatch(asColumns[Index], string.Format("^{0}[^{0}].*[^{0}]{0}$", Escape))) // If "Text" is sourrounded by quotes (but ignore double quotes => "Leave ""inside"" quotes")
{
asColumns[Index] = asColumns[Index].Substring(1, asColumns[Index].Length - 2); // "Text" => Text
}
asColumns[Index] = asColumns[Index].Replace(Escape + Escape, Escape); // Remove double quotes ('My ""special"" text' => 'My "special" text')
if (asColumns[Index] == null) asColumns[Index] = "";
}
The output array is asColumns