Append Text to Existing Text File C#.Net

In today's article I will show you a simple tutorial with an example how you can append the text to an existing file in c#.net. In this example I will use windows application with c#.net. Now for example fist we will create a folder and add a text file at that location with sone text. 

In above location I have added a text file. In this file I have added some text. So, we will append the user text with the existing text. Let's check the content of the text. 

After this we will create a new windows application with C#.Net. In this application we will add a form, and, in this form, we will add a textbox and a button control. 

Now let's add the click event of button control and add the below code in it. 

 string filePath = "D:\\DemoProject\\DemoFolder\\codemantra99.txt";
if (File.Exists(filePath))
{
    File.AppendAllText(filePath, txtUserText.Text + Environment.NewLine);
    lblMessage.Text = "Text appended successfully.";
}
else
{
    lblMessage.Text = "Error!!!! Folder path does not exists.";
} 

In above code i have taken the path of the file in a string type variable. After defining the path i have validated the file exists or not. If file does not exist will display a message to user. File.AppendAllText(path, text) to append the user entered text in existing text file. to append the text in a new line Environment.NewLine have been added. Now we have done. lets run the code and check the output.

Now let's add some text and click on submit button 

Now let's check the text file for final output.

append-text-to-existing-file-c-net.zip 32KB