Group
File Handling in C#
Objective
1. The program expects a CSV file with four values per line: name, surname, city, and age.
2. Each data block should be enclosed in quotes, and the values should be separated by commas.
3. The output will be a new text file with each data block from the CSV file written on a new line.
4. Run the program by passing the input CSV file name as a parameter.
Example usage:
csvToText input.csv
The CSV ("Comma Separated Values") is an exchange format used by many spreadsheet and database management systems. It consists of a series of comma-separated values enclosed in quotation marks, although there are variants that do not use quotes or use semicolons as separators. Often, the values are not enclosed in quotes. An example file would be:
"John", "López Pérez," "Alicante", 25
"Antonio", "Pérez López", "Madrid", 27
You should create a program that reads a CSV file as shown above, with four data blocks (the first three are text and the last one is numeric), each of which is on a separate line. The program should generate a text file where each entry contains a line like this:
John
Pérez López
Alicante
25
Antonio
Pérez López
Madrid
27
Example C# Exercise
Show C# Code
using System;
using System.IO;
class CSVToTextConverter
{
// Main method where the program starts execution
static void Main(string[] args)
{
// Check if the user has provided the necessary file name argument
if (args.Length != 1)
{
Console.WriteLine("Usage: csvToText ");
return;
}
// Get the input CSV file name from the command line arguments
string inputFileName = args[0];
// Check if the specified file exists
if (!File.Exists(inputFileName))
{
Console.WriteLine("The specified file does not exist.");
return;
}
// Define the output file name by changing the extension to .txt
string outputFileName = Path.ChangeExtension(inputFileName, ".txt");
try
{
// Open the input CSV file for reading
using (StreamReader reader = new StreamReader(inputFileName))
{
// Open the output text file for writing
using (StreamWriter writer = new StreamWriter(outputFileName))
{
string line;
// Read each line from the CSV file
while ((line = reader.ReadLine()) != null)
{
// Split the CSV line by commas, assuming values are enclosed in quotes
string[] data = line.Split(new char[] { ',' }, StringSplitOptions.None);
// Loop through the data array and write each value to the output file
foreach (var value in data)
{
// Remove quotes around values if present
string cleanValue = value.Trim('"').Trim();
// Write the cleaned value to the output file on a new line
writer.WriteLine(cleanValue);
}
}
}
}
// Inform the user that the file has been successfully created
Console.WriteLine($"Text file created successfully: {outputFileName}");
}
catch (Exception ex)
{
// Handle any errors that occur during file reading or writing
Console.WriteLine("An error occurred: " + ex.Message);
}
}
}
Output
//For an input CSV file named input.csv with the following content:
"John", "López Pérez", "Alicante", 25
"Antonio", "Pérez López", "Madrid", 27
//The output text file (input.txt) will contain:
John
López Pérez
Alicante
25
Antonio
Pérez López
Madrid
27