c# write on file code example
Example 1: asp.net c# write string to text file
using (StreamWriter writer = new StreamWriter("email.txt", true)) //// true to append data to the file
{
writer.WriteLine("your_data");
}
Example 2: c# write file
class WriteTextFile
{
static void Main()
{
// These examples assume a "C:\Users\Public\TestFolder" folder on your machine.
// You can modify the path if necessary.
// Example #1: Write an array of strings to a file.
// Create a string array that consists of three lines.
string[] lines = { "First line", "Second line", "Third line" };
// WriteAllLines creates a file, writes a collection of strings to the file,
// and then closes the file. You do NOT need to call Flush() or Close().
System.IO.File.WriteAllLines(@"C:\Users\Public\TestFolder\WriteLines.txt", lines);
// Example #2: Write one string to a text file.
string text = "A class is the most powerful data type in C#. Like a structure, " +
"a class defines the data and behavior of the data type. ";
// WriteAllText creates a file, writes the specified string to the file,
// and then closes the file. You do NOT need to call Flush() or Close().
System.IO.File.WriteAllText(@"C:\Users\Public\TestFolder\WriteText.txt", text);
// Example #3: Write only some strings in an array to a file.
// The using statement automatically flushes AND CLOSES the stream and calls
// IDisposable.Dispose on the stream object.
// NOTE: do not use FileStream for text files because it writes bytes, but StreamWriter
// encodes the output as text.
using (System.IO.StreamWriter file =
new System.IO.StreamWriter(@"C:\Users\Public\TestFolder\WriteLines2.txt"))
{
foreach (string line in lines)
{
// If the line doesn't contain the word 'Second', write the line to the file.
if (!line.Contains("Second"))
{
file.WriteLine(line);
}
}
}
// Example #4: Append new text to an existing file.
// The using statement automatically flushes AND CLOSES the stream and calls
// IDisposable.Dispose on the stream object.
using (System.IO.StreamWriter file =
new System.IO.StreamWriter(@"C:\Users\Public\TestFolder\WriteLines2.txt", true))
{
file.WriteLine("Fourth line");
}
}
}
//Output (to WriteLines.txt):
// First line
// Second line
// Third line
//Output (to WriteText.txt):
// A class is the most powerful data type in C#. Like a structure, a class defines the data and behavior of the data type.
//Output to WriteLines2.txt after Example #3:
// First line
// Third line
//Output to WriteLines2.txt after Example #4:
// First line
// Third line
// Fourth line
Example 3: aprire e scrivere un file in c#
try
{
//Pass the filepath and filename to the StreamWriter Constructor
StreamWriter sw = new StreamWriter("C:\\Test.txt");
//Write a line of text
sw.WriteLine("Hello World!!");
//Write a second line of text
sw.WriteLine("From the StreamWriter class");
//Close the file
sw.Close();
}
catch(Exception e)
{
Console.WriteLine("Exception: " + e.Message);
}
finally
{
Console.WriteLine("Executing finally block.");
}
Example 4: aprire e scrivere un file in c#
String line;
try
{
//Pass the file path and file name to the StreamReader constructor
StreamReader sr = new StreamReader("C:\\Sample.txt");
//Read the first line of text
line = sr.ReadLine();
//Continue to read until you reach end of file
while (line != null)
{
//write the lie to console window
Console.WriteLine(line);
//Read the next line
line = sr.ReadLine();
}
//close the file
sr.Close();
Console.ReadLine();
}
catch(Exception e)
{
Console.WriteLine("Exception: " + e.Message);
}
finally
{
Console.WriteLine("Executing finally block.");
}