How to Read a Text File in C#
In C# ‘File’ class provides static methods to read given text file data. The File.ReadAllText() method opens a text file, reads all the text present in the file into a string variable and then closes the file.
1.Read whole data of Text file:
// Read entire text file content in one string
string text = File.ReadAllText(textFileCompeltePath);
Console.WriteLine(text);2.Read data line by line:
The File.ReadAllLines() method opens a text file, reads all lines of the file into a string array, and then closes the file. The following code snippet reads a text file into an array of strings.
string [] lines = File.ReadAllLines(textFileCompletePath);
foreach (string line in lines)
Console.WriteLine(line);3. Read a text file is using a StreamReader:
One more way to read a text file is using a StreamReader class that implements a TextReader and reads characters from a byte stream in a particular encoding. The ReadLine method of StreamReader reads one line at a time.
using System;
using System.IO;
namespace ReadTextFromFile {
class Program {
static readonly string rootFolder = @ "C:\Temp\Data\";
static readonly string textFile = @ "C:\Data\Student.txt";
static void Main(string[] args) {
if (File.Exists(textFileCompletePath))
{
// Read entire text file content in one GO
string text = File.ReadAllText(textFileCompletePath);
Console.WriteLine(text);
}
if (File.Exists(textFileCompletePath))
{
// Read a text file data line by line.
string[] lines = File.ReadAllLines(textFileCompletePath);
foreach(string line in lines)
Console.WriteLine(line);
}
if (File.Exists(textFileCompletePath))
{
// Read file using StreamReader. Reads file line by line
using(StreamReader file = new StreamReader(textFileCompletePath))
{
int counter = 0;
string ln;
while ((ln = file.ReadLine()) != null) {
Console.WriteLine(ln);
counter++;
}
file.Close();
Console.WriteLine($ "File has {counter} lines.");
}
}
Console.ReadKey();
}
}
}Till now we learned about reading of data from text file, below we, learn more about other methods of File class.
Working With File Class Methods in C#:
C# File Class methods:
In C#, ‘File’ class provides many static methods for moving, copying, and deleting files. These Static methods involve moving a file and copying and deleting a file also. Let’s check out the chart below.
List of the common File class methods:
| Sr. No. | Method Name | Description |
|---|---|---|
| 1. | Copy | This method is used to copy given file to the specified location. |
| 2. | Create | This method is used to create a file in the specified path. |
| 3. | Delete | This method is used to Delete a file. |
| 4. | Open | This method is used to return a filestream object at the specified path. |
| 5. | Move | Moves a given file to a new location. We can also specify a different or new name for the file in the new location. |
| 6. | Exists | This method is used to check whether the specified file exists or not. It returns boolean=true if file exists else will return false. |
| 7. | OpenWrite | It is used to opens an existing file or creates a new file for writing. |
| 8. | OpenRead | It is used to opens an existing file for reading. |
We hope with above post you learned how to use the File class in C# and how to read a text file data using various methods of C#. Check more on above methods of File class in C#.
