Where is the text file once I publish the program?

Where is the text file once I publish the program?

I made a program that takes user input from a text box and writes it to a
text file when a button is pressed. When I finally published it, I wasn't
able to find the text files anywhere. Here's the code:
private void button1_Click_1(object sender, EventArgs e)
{
using (StreamWriter sw1 = new StreamWriter("DataNames.txt",true))
{
sw1.WriteLine(textBox1.Text);
}
Where is the file, or how can I make it write to a certain place?