What is the difference between an absolute and a relative path?

Question

I am asking because I am working on a project for school. Yes this is homework. But, I'm trying to understand a little bit more, though.

This is one example of what is being asked.

• When the user clicks the “Save” button, write the selected record to the file specified in txtFilePath (absolute path not relative) without truncating the values currently inside.

This is what I have,

private void button2_Click(object sender, EventArgs e)
{
    if (saveFileDialog1.ShowDialog() == DialogResult.OK)
    {
        StreamWriter myWriter = new StreamWriter(saveFileDialog1.FileName);
        myWriter.Write(txtFilePath.Text);
        myWriter.Close();
    }
}

Now, I don't understand if I am doing this right. I know when I save it to my desktop and I delete it from my listbox and when I try to reload it again nothing shows up. This is what I have on my form,

private void button1_Click(object sender, EventArgs e)
{
    if (openFileDialog1.ShowDialog() == DialogResult.OK)
    {
        StreamReader myReader = new StreamReader(openFileDialog1.FileName);
        txtFilePath.Text = openFileDialog1.FileName;
        txtFilePath.Text = myReader.ReadToEnd();
        myReader.Close();
    }
}    

And this is the load,

private void Form1_Load(object sender, EventArgs e)
{
    string[] myFiles = Directory.GetFiles("C:\\");
    foreach (string filename in myFiles)
    {
        FileInfo file = new FileInfo(filename);
        employeeList.Items.Add(file.Name);
    }

    //...

Can someone please help me make sense of this?

Answer 1

Say you were giving directions to a spot. You have two methods you can describe getting to the location:

• Relative to where you stand,
• Relative to a landmark.

Both get you to the same location, but the former doesn't always work ("take a left, then a right, go through two lights then take another right" wouldn't necessarily work from the next town over, but works from where you stand). That's essentially the difference.

If you have C:\Windows\System32, that's an absolute path. If you have Windows\System32, it will only work so long as you're starting from C:\. If you start in C:\Program Files you would need a ..\ to get there correctly.

However, no matter where you are on the hard drive, C:\Windows\System32\ is a definitive way to get to that folder.